Hey!
For reliability and longevity go for the 3070 or an RX 6800XT for a GPU - although you could also get by with a 2060 or greater without any performance impacts for streaming! I'm an AMD CPU fanboy so my recommendation would be a 7600x, although a 12700 or better would also be fine in terms of intel if you'd rather go team blue! For ram, I'd go 32GB of 3600 MHz or higher - you could get by with 16GB, but for future-proofing I'd go for 32GB. Apart from this, go with a decent air cooler or if you prefer watercooling, then a 240mm AIO.