Welcome to 2+2
This sounds like a trite answer, but in reality, you have to get good at poker. You want to be one of the two best players at any table you sit, if possible. Since nobody starts out good at poker, everyone starts near zero and learns the things they don't know. As a pure beginner, you end up knowing "learn everything". Likely you're starting preflop. Then the flop. Then turn/river decisions, which become easier if the first two streets are right. Once you figure the basics out, you have to find the things you need to improve. For me, spots that are confusing (that come up often) are a good indication of places to work on your game.
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I had a big problem where I would play smart poker for an hour, 2 hours, but after that I would get mentally drained.
Knowing how to play poker, you then have to be able to do it every hand. The mental game stuff takes a while. It is easier to keep your mind good when you have really good poker skills.
My question to you is "what do you need to improve in poker?" The most valuable things to fix are things that are expensive mistakes that come up often.