Game running choppy frequently even with very high fps

Recently, I got a new PC, so I plugged it in, installed the drivers and hopped on a game to see this weird issue, where the game runs on 144+ fps and the visually lowers to very low fps but the fps counter still indicates 144+. There is a similar issue with my mouse, when on a game, the mouse runs at 60hz but I can see the game running at 144hz.

I really need help so if any of you could help me, I would greatly appreciate it. Thank you.