For the computer novice a prebuilt computer is the smarter way to go. The computer will work on day one and if you encounter a problem there is going to be someone to phone for help. Building it yourself will cost you more and this is even if you place no dollar value on the time spent putting it together and troubleshooting problems, including updating the BIOS and device drivers for everything.
The PCPartPicker Part List includes the XFX Radeon RX 6800 graphics card. Check the reviews by those you have bought XFX boards and you will find that the company provides no customer support of any kind, even for DOA boards. The AMD drivers are a problem for many gamers who experience sudden crashes of games and even of the operating system. It is not what you know but what you know that is not so that causes grief, to paraphrase Yogi Berra.