If I get an out of state internship during the summer I am applying is that going to be a problems? Like what kind of information/materials do I need for secondary maybe?
you should be fine. as long as you'll have access to internet and phone, obviously. just make sure to bring EVERYTHING you think you could possibly need with you--paperwork, contact numbers, etc. pack heavily!
i'm not quite sure what you mean by "materials." if you're curious about secondary prompts, etc. you should check out some of the school-specific threads.
yes, secondaries are submitted online. to my knowledge they won't require extra LORs. those should be submitted with your primary.