While Iām a big fan of building PCs Iāll give a bit of caution, as due to silicone shortages itās still really hard to get your hands on a decent graphics card. For the last year or so itās actually been cheaper, sometimes a lot cheaper, to buy a pre-built PC with a graphics card included.
That said, the AMD Ryzen CPUs are fantastic for gaming and most other tasks, and are a great balance between price and performance. I donāt know about water cooling, I whacked a tower heatsink onto mine and itās near inaudible, even when gaming.
32GB of RAM and an M.2 SSD are definitely recommended, although you might be able to get away with 16GB depending on what youāre using it for.