Need some guide or snippet, demo to transfer SPL token out from program's PDA account

Question

My goal is to have my own program receive any Token, store in one of PDAs of program. Then transfer they out to end user wallet.

Currently I successfully send token to program's PDA, but still not able to transfer token out. What I have try is following this guide: https://www.quicknode.com/guides/solana-development/anchor/transfer-tokens but it turn out that this guide just send token from one source account to destination, have nothing to do with program's PDA.

Can anyone share some proper guide or snippet, demo?

Thanks