He's still only 2 years old. You may be comparing his potty training progress to your first child, and now is a great time to realize how different children can be, even if they have the same parents and are raised in the same home, the same way.
He's not ready, and you're struggling over a futile issue. Potty training involves more than just physical actions; the emotional development has to be there too. He can see with his eyes. Are you frustrated that he can't read yet? He can grab things with his little hands. Are you frustrated that he can't draw a portrait? Yes, he can poop. No, he can't comprehend the plumbing and septic tanks. I know changing diapers gets old after several years of having young kids, but that's no reason to force your child to sit on the toilet until he does what you want him to do.
And bribing a child with a toy is usually not the right answer, regardless of what you're trying to accomplish. You're offering a reward for a biological action. Children should not earn toys for eating, using the potty correctly, wearing a helmet while on anything with wheels, and following basic safety rules (looking twice and crossing a street at a crosswalk, holding a grownup's hand in a parking lot, etc). A toy is a gift. If you start using toys as rewards for basic stuff, you're in for a very bumpy ride, when they start demanding stuff for doing their homework or passing a test when they're older. Your child's reward should be your smile, your reasonable congratulations (not jumping up and down screaming like you won the lottery, but "good job, buddy!"), and your pleasant interaction.