What are all the parts needed to build a good gaming PC?

I've never built a PC before, and have limited knowledge about parts, but I want to build a primarily gaming/video/movie PC. I dont actually play many games, but the few I do: Terraria/Minecraft/Runescape being the biggest, tend to be on medium to low settings and lag a lot.
I also stream movies frequently and watch a lot of youtube videos. I'm looking to build a pretty damn good PC that is fast and reliable for these activities, and my budget is around $900-$1100 preferred.
I'd like to know what I need or recommended brands so I can start shopping around online for deals as I'm transferring to a state college in the next 3 months and want this built before hand.
Thanks in advanced!
Added (1). EDIT* 60FPS and at least 1080p are a must, although I would love to be able to play/watch in 4k if possible in this budget

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