what should i upgrade first if im aiming to increase fps and reduce fps drops? (specs in description)

cpu: intel i5 4670

gpu: nvidia gtx 1050ti

installed ram: 24gb

motherboard: asus z87m plus

i have an ssd if that matters, i'm new to this so if i missed out any important specs pls let me know :)

i currently run about 120-150 fps in valorant with frequent screen tears and occasional freezing. any opinion on what my pc's weakest link is? its like a 10 year old office pc but i'm not able to buy a whole new one so i have to make do with upgrading the parts slowly.

thanks in advance!