Omg. I never thought I'd come to a point where I had to read the İndonesian to understand the English :D
Since these are shallot and garlic respectively, the what are red onion and white onion?
White onion is bawang bombay.
Can you also say bawang merah dan putih?
I don't think so, 'cause "bawang merah dan putih" means "an onion which has two colors (red and white)"