What does Se Puede mean in English?

He or she can... or He or she is able to... It can also mean 'you can' when being polite, and used in a question, it can mean 'can you (or he or she)...?'
"Puede" can be either the second person singular formal or third person singular conjugation of the verb "poder" which means "to be able to".

"Puede" means either "you can" or "s/he can"

I Think the Translation for Sí, se Puede is "Yes we Can" or "Yes you Can"