How the heck do I beat him?

I’ve tried at least 10x and beat him twice, then it sends me straight to Bowser, but my health is already at 2! To be honest I’m unsure how the badges work, or which ones I should have. Help!

I’ve tried at least 10x and beat him twice, then it sends me straight to Bowser, but my health is already at 2! To be honest I’m unsure how the badges work, or which ones I should have. Help!