I’m having anxiety.. I need advice.

So my dad started doing crystal meth 5 years ago.. around the same time I graduated high school. We have rarely spoken and he basically ignores me everytime I try to reach out. During this 5 year span he has had two children with his girlfriend who is also on drugs. They were both arrested about a month ago on drug charges. Today my dad reached out to me and asked if I would take custody of my two baby brothers so they wouldn’t be taken by the state. I feel torn. I don’t want them to go to fosters homes but realistically I can’t take care of two young children. I work a minimum wage job and can barely afford to support myself. Between classes and working 3rd shift I just don’t see how it can work. I feel like such a bad person for saying no.. and I feel like everyone else thinks the same. I just don’t feel like I could even give them the life they deserve. Any thoughts or advice would help.