Low Supply?

Ab

I’ve been seeing a few people say “supplementing is why your supply is low” but if my baby is hungry and I have no milk, what do I do? Not trying to be rude but if they are obviously still hungry and crying after each breastfeeding session then are they saying to just let them stay hungry? I am really struggling with low supply, would LOVE to exclusively breastfeed but also cannot watch my baby be hungry.