rtx 3090 low fps

Hi! Recently i bought RTX 3090 for a great deal, but its performing bad in my PC. I think it's the CPU problem...if im correct i need upgrade advice for stronger one! My goal is to play everything on max settings and 144FPS! Thanks in advance! (oh also im just gaming so i need cpu only for that...

I feel like my PC is running kind of slow. Tried watching some videos about BIOS optimizations, but I don't really understand them and don't want to mess up something. (The PC Is the GA35DX-XB999 configuration) Score in 3DMark is 17,139 OS: Windows 11 Pro MB: Asus ROG STRIX X570 (not sure...