Dell Vostro 3500 Gaming Issues

Hello there, 
I hope y'all doing well I have Dell Vostro 15 3500 and it works fine but in gaming, I always face a problem that my GPU usage is unstable and the CPU usage is too low and I couldn't find a solution for this problem can some one help me? 


this problem is in valorant, BFV, and any other game actually 


specs 
processor: inter core i5 1135G7 @2.40 GHz
Ram : 8gb ddr4
graphics card: Nvidia Mx330 gddr5 2gb
256 GB SSD 
1 TB HDD