if i ask you, if you would buy bitcoin right now, where would you go? its just a question
If you don't mind KYC, you can register for Binance, KuCoin, or other CEX exchanges. But if you don't want to do KYC, you can choose DEX, like hodlhold.com, or other options.
You should have a goal before buying Bitcoin, whether for trading or investing because both are different. If you want to trade, you have to be able to determine when you can buy Bitcoin at a low price, sell it at a high price, and repeat this process to get big profits.
If you want to invest, you don't need to do that. Just focus on buying Bitcoin once a week or once a month and do that continuously.
But you should learn about analysis first to determine when to buy and sell. The important thing is that you can be calm when the price goes down and see it as an opportunity to buy Bitcoin again.
According to what you mentioned already, the first and foremost step is to own a wallet probably a mixture of hot and cold wallets and know how to buy your preferred coins to trade with and how to withdraw, transfer or deposit your funds.
Then, that's when the YouTube videos would do well to teach all other things like how to set up a trading account on any decentralized exchange and then the safest or easiest technique to trade as a newbie until you get to a professional stage where other techniques are exposed with experience and more acquisition of knowledge.