@entomashadoll For me the difficult part is getting the libffmpeg-file.
https://github.com/Ld-Hagen/fix-opera-linux-ffmpeg-widevine has a script doing it all for you; get the ligffmpeg and copy it to the right lcoation. You run it every time you update opera. Or you could try the snap-version (as wonghow suggests) or the flatpack-version. Mint prefers flatpaks to snaps, but my experience with the opera flatpak was not good.
As long as you make a timeshift snapshot before changing anything you can always go back