You can go to partpicker.com and you would really only need to buy the following. CPU, Motherboard, Power Supply, Graphics Processing Unit (GPU), Case, Operating System (Recommend Windows 10 64-bit (Pro or Home Edition) The Pro edition lets you upgrade your ram to a higher capacity, and also the monitor, mouse and keyboard. You don't really need a fancy monitor, mouse or keyboard, and most parts are available at newegg.com ncix.com amazon.com tigerdirect.com or ebay. I recommend getting brand new components as the warranty will cover any DOA. Also, for the video card, you can start at a 1050Ti or an RX 560, but with at least 4GB of Video Ram in either graphics card. Also, I recommend at least 8GB of RAM. And of course, go to the Motherboard's Manufacturer website and read the manual. The manual will tell you what type of Ram you should get. The newest computers use DDR4 Ram, so if your motherboard uses this, I recommend either the 2133 or 2400 MHz DDR4 Ram, since they have almost the same price, but note that higher numbers are better, so if higher speed ram costs the same as the lower speed, get the higher speed ram. Also, as far as ram goes, GSkill, Corsair, Kingston Hyper X are good. I would never get Patriot though. Everything else might be cheaper, but the before mentioned have heatsinks, which help cool your pc and keep your pc running fast. If you need more help, you can ask any of us here or via message.