How to potty train boys?

I need some advice on best ways to potty train a boy! He’s 2 1/2 almost. We’ve been struggling. I can get him to sit on the potty but he won’t do anything and wants to get up as soon as he sits down. Does this mean he’s not ready? Anything I can do to help him be ready? I work from home and preschools in my area won’t take him if he is still in a diaper (they take them as young as 2). It’s getting too much to have him home every day each week. I’d ideal like to get him potty trained and him go to preschool 2-3 days a week. HELP!!