I say this as someone who still hasn't gotten around to learning how to use a wallet. I should probably do that.
Imperative. Download a good mobile wallet and move your stack. I recommend Samourai Wallet if you are on android. It's not as complicated as it looks. Just remember to always write down your seed phrase and pin number and keep in a safe, secure place.
Edit. If you have a significant amount of BTC, you need to spend the money and get a hardware wallet. Trezor or Coldcard. Cold storage is more secure.