What country are you in? The US, or elsewhere?
If you are in the US, what is your mom’s status? With a green card she can work here (except for certain government jobs that specifically require citizenship). What is your status?
If you are outside the US now, are you a US citizen now living abroad with your mom and the step dad, or are you an international applicant who has moved from one non-US country to another? The information about student loans, and about college admission in general, is very different for non-US applicants.