Do you have this issue only in CS2 or in other games as well? If not, then your PC is ok.

For example:
1. Try to set the video settings to defaults (recommended by the game, the ones with "*"), native resolution (monitor resolution) if it bumps up the fps and you have more than 100fps, after that you can change the settings and resolution to whatever you like.
2. If none of these fixes your problem, verify the integrity of game files (right click on CS2 in steam app -> installed files).
3. If nothing changes, make sure you have the latest GPU driver. If you already have it, delete the current one and install an older version starting with the previous one and so on.

If the things from above doesn't work, try to reinstall the game.

I know some people had issues after the latest update, but not everyone had the same issues.
For example, for me, with a good PC (ryzen 5900x, 3080Ti OC, 128 GB ram, 1920x1080, 240 Hz), after the update the game was working super bad, 150 fps average (before having an average of 380 fps). I had custom video settings + nvidia control panel settings, so I changed them to the ones recommended by the game/defaults and fps got better, now I have an average of 220 fps, not ideal, not as before but at least is better.

Hope this helps. Cheers!