BTC noob here, Cashapp question.

I'm relatively new and somewhat passive in my btc investing. I believe now is a good time to start buy and holding on as I think the long game is where the payout will be.

Question is, is Cashapp a good method for buying and keeping my btc? I like to throw in roughly $10-$25 a week on it, but would hate to turn out that it is a compromise exchanges.

I've heard people talking about taking your investment out of exchanges and put in cold storage. What does that mean?

I would appreciate any insight or tips.

Thank you in advance.