When I have Tobias Beckett on Escape Craft which starts game docked with Scum Falcon, can I use Tobias'es ability.

No, from the rules reference on Reserve:

Quote

• The abilities of a ship in reserve are inactive unless the ability explicitly allows it to be used while it is in reserve.
• A ship that is docked is placed in reserve.

Now you could place the escape craft in the play area undocked and at range 0 of the scum falcon at setup, then dock the escape craft in the system phase of round 1, but you do need to place it in the play area in order for Beckett's ability to trigger.

No, you can't.

Crew or other upgrades on docked ships don't affect the broader game, unless they specifically describe working while docked.

However, you could deploy Beckett's EC and the Falcon touching each other, and immediately dock them in the first system phase.

Thank You both I see that I can sacrifice Initiative 6 on Han in order to use Tobias on Escape Craft piloted by Lando nice workaround