There is heaps and it can get really complicated but I've learnt the best keep it very simple. I would start by learning and mastering 3 of the basic but most central concepts:
Market Structure
https://tradeproacademy.com/definition-of-market-structure/
Support and resistance
https://www.investopedia.com/trading/support-and-resistance-basics/
Diagonal Trendlines
https://www.thebalancemoney.com/how-to-effectively-use-trendlines-in-your-trading-1030884#:~:text=The%20Basics%20of%20Trendlines&text=Trendlines%20are%20simply%20diagonal%20lines,go%20in%20a%20given%20timeframe.
One thing that people also forget is that volume is often just as important as price analysis, they go hand in hand, so would read up on that too:
https://www.investopedia.com/articles/technical/02/010702.asp
