how to remove stuck disc?

Since you don't specify the model, you are unlikely to get a comprehensive answer. Check the user manual for "manual disk eject" or something similar. On some trays, there is a pin-hole you can insert (e.g.) an unfolded paper-clip end into, which manually unlocks the tray, but this is not universal.

Best bet is to consult the manufacturer's documentation.

Sparks (the Plumber)
May 2018