Champion 2k in storage for three years. Advice starting it?

If not too late remove the spark plug and pour in a tiny bit of motor oil. Pull the starter slowly to coat the walls.

Like others said drain fuel tank and if easy drain the carb. If it runs on starting fluid or brake cleaner but dies instantly then clean the carb. Or if it looks simple just clean the carb now. It might run but not at full potential if you have a partial blockage.