I cant download codecs from software center


i can see them but opening them does show this error not for all though

Most of the ones that cannot be downloaded that way seem to be the ones that are restricted and not available directly from fedora.

Almost all can be downloaded by dnf from rpmfusion.
if you have the rpmfusion repos enabled then downloading the ffmpeg, ffmpeg-libs, lame, and gstreamer1-nonfree packages should give you all that are needed for most use.

I have these installed from rpmfusion and while some are not av related I have had no issues with playback of almost any audio or video format. All were installed using dnf, many as dependencies.

audacity-freeworld.x86_64                            3.1.3-3.fc36                           @rpmfusion-free           
compat-ffmpeg28.x86_64                               2.8.20-1.fc36                          @rpmfusion-free-updates   
compat-ffmpeg4.x86_64                                4.4.2-6.fc36                           @rpmfusion-free-updates   
dvdstyler.x86_64                                     2:3.2.1-2.fc36                         @rpmfusion-free           
faad2-libs.x86_64                                    1:2.10.0-3.fc36                        @rpmfusion-free           
ffmpeg.x86_64                                        5.0.1-3.fc36                           @rpmfusion-free           
ffmpeg-devel.x86_64                                  5.0.1-3.fc36                           @rpmfusion-free           
ffmpeg-libs.x86_64                                   5.0.1-3.fc36                           @rpmfusion-free           
gstreamer1-plugins-bad-freeworld.x86_64              1:1.20.3-1.fc36                        @rpmfusion-free-updates   
gstreamer1-plugins-ugly.x86_64                       1:1.20.3-1.fc36                        @rpmfusion-free-updates   
intel-media-driver.x86_64                            22.3.1-1.fc36.2                        @rpmfusion-nonfree        
libaacs.x86_64                                       0.11.1-1.fc36                          @rpmfusion-free           
libavdevice.x86_64                                   5.0.1-3.fc36                           @rpmfusion-free           
libcapsimage.x86_64                                  2.0.0-26.fc36                          @rpmfusion-nonfree        
libcapsimage-devel.x86_64                            2.0.0-26.fc36                          @rpmfusion-nonfree        
libdca.x86_64                                        0.0.7-5.fc36                           @rpmfusion-free           
libde265.x86_64                                      1.0.8-5.fc36                           @rpmfusion-free           
libdvdcss.x86_64                                     1.4.3-3.fc36                           @rpmfusion-free-tainted   
libfreeaptx.x86_64                                   0.1.1-3.fc36                           @rpmfusion-free           
libmms.x86_64                                        0.6.4-17.fc36                          @rpmfusion-free           
libquicktime.x86_64                                  1.2.4-54.124.20210720git2729591.fc36   @rpmfusion-free           
librtmp.x86_64                                       2.4-21.20190330.gitc5f04a5.fc36        @rpmfusion-free           
libva-intel-driver.x86_64                            2.4.1-8.fc36                           @rpmfusion-free           
live555.x86_64                                       2022.02.07-1.fc36                      @rpmfusion-free           
lxdvdrip.x86_64                                      1.77-15.fc36                           @rpmfusion-free           
mencoder.x86_64                                      1.5-1.fc36                             @rpmfusion-free           
mjpegtools.x86_64                                    2.2.1-2.fc36                           @rpmfusion-free           
mjpegtools-lav.x86_64                                2.2.1-2.fc36                           @rpmfusion-free           
mjpegtools-libs.x86_64                               2.2.1-2.fc36                           @rpmfusion-free           
mplayer-common.x86_64                                1.5-1.fc36                             @rpmfusion-free           
mpv.x86_64                                           0.34.1-3.fc36                          @rpmfusion-free           
opencore-amr.x86_64                                  0.1.5-14.fc36                          @rpmfusion-free           
pipewire-codec-aptx.x86_64                           0.3.58-1.fc36                          @rpmfusion-free-updates   
rpmfusion-free-appstream-data.noarch                 36-4.fc36                              @rpmfusion-free           
rpmfusion-free-obsolete-packages.noarch              35-1.fc36                              @rpmfusion-free           
rpmfusion-nonfree-appstream-data.noarch              36-3.fc36                              @rpmfusion-nonfree        
simplescreenrecorder.x86_64                          0.4.4-1.fc36                           @rpmfusion-free           
svt-hevc-libs.x86_64                                 1.5.1-3.fc36                           @rpmfusion-free           
vcdimager.x86_64                                     2.0.1-12.fc36                          @rpmfusion-free           
vcdimager-libs.x86_64                                2.0.1-12.fc36                          @rpmfusion-free           
vlc.x86_64                                           1:3.0.17.4-1.fc36                      @rpmfusion-free-updates   
vlc-core.x86_64                                      1:3.0.17.4-1.fc36                      @rpmfusion-free-updates   
vo-amrwbenc.x86_64                                   0.1.3-16.fc36                          @rpmfusion-free           
wxsvg.x86_64                                         1.5.24-1.fc36                          @rpmfusion-free-updates   
x264-libs.x86_64                                     0.163-6.20210613git5db6aa6.fc36        @rpmfusion-free           
x265-libs.x86_64                                     3.5-3.fc36                             @rpmfusion-free           
xmms2-faad.x86_64                                    0.8-35.fc36                            @rpmfusion-free           
xmms2-mms.x86_64                                     0.8-35.fc36                            @rpmfusion-free           
xmms2-mp4.x86_64                                     0.8-35.fc36                            @rpmfusion-free