Low fps on valorant even though I got a decent pc

I got a pc better than the minimum requirements for valorant an i3 6th gen 8gb ram and 520 hd graphics card it's not good but it's just better than the stayed minimum requirements for the game I play on lowest settings possible and still sometime my fps drops to 10-20 range usually it stays around in the 60-80 range during buy round is there anything I can do for a stable 60 fps or less fps drops?