Selecting multiple clips

I have like 50 clips and i want to select them all and put a filter on them but i don’t know how. Any help is appreciated.

If all the clips are in the timeline on the same track, select the track ‘head’ (far left Olive section with the track action icons, will turn blue when ‘selected’) and apply the filter to that. This will affect all clips on that track.
If not, then no.