1. Can a transferred token or coin be reversed?
For most coins/tokens, the answer is no. You can't revert a confirmed transaction. However, the answer depends on the chain you are using, if it's centralized then the entity in control can do whatever they want with the coins.
2. If I send out BTC to a family friend can it get stuck and can I resend adding more gas fee?.
Yes, a bitcoin transaction can
get stuck if it's paying a low fee while the network is congested with other transactions paying higher fees.
You can increase the fee rate to accelerate the confirmation
if the initial transaction was flagged as rbf. Or by spending one if its outputs that you control (which is known as cpfp).
Gas is for ethereum, for bitcoin it's fee rate expressed in sat/vByte.