how much would a basic pc build cost??

I'm thinking of getting myself a pc but idk where to start!! I'm more interested in the building & customising part because I love things like that, and I love how those all-white ones with loads of lights look. I don't need it to be super powerful, I only really play Roblox, Minecraft and genshin, but I would like to be able to play more intense games if I wanted to one day!! does anyone have any recommendations of where to buy parts, or what to look for?? I don't know anything about this bc I've used Macs my whole life ahah!!