Oh lordy. Two years old isn't quite putting it together yet. You need to rephrase it honestly, and provide visual enforcement.

Example:

"If you eat your veggies you get a cookie."

Put a small cookie on a plate where she can see it just out of her reach.

Kid: cries, demands cookie

Parent: "of course you can have the cookie AFTER you eat your veggies."

Kid cries more.

Parent: "veggies first, cookie second"

Kid cries more.

Parent: "hooow many bites of veggies do we have here? Four? Wow! You can do four."

Etc rinse repeat. It's a long process, but eventually you'll train them to understand succession.

Masks are a different thing. I sincerely just waited for him to want to go somewhere and upheld the rules. He fought for awhile, but eventually gave in after a few weeks of no park.