What kind of mindset should I have to stay in Bitcoin? And I think Bitcoin is about to hit the highest price ever, so how should I plan my dca strategy?
It is not too late. Your DCA strategy will depend on the amount of money you are earning and the period of time you are given. If you earn weekly, you should DCA weekly. If you earn money, you should DCA monthly.
The transaction fee is high right now, you can use lightning network. Many exchanges are having lightning network and you can use it with a lightning network wallet.
If the amount has grown, then send it to a noncustodial wallet.