Hi Chloyeee
🙂if you are thinking of building a water cooling loop you will need a few basic components...A pump...a reservoir...a radiator and some tubing and fittings for connecting things. What you chose might be affected by what case you have and what components can comfortably fit inside it.
Since you would need the basic components for any loop you build, adding one more piece...a block to cool the CPU... would not be much more effort and cooling the CPU too can give you great temperatures and maybe a performance boost if OCing.
are you looking for a recommendation of specific parts?