Being Ostracized in Research Group
Based on the updates, there are a few things I can offer in terms of advice. The first is that given it's a short amount of time remaining on your term, stick it out. Especially if this is going to impact your college credits/marks/etc. Sure, it's a crappy situation but try to make the best out of it as not to impact your marks or the progress of your degree.

Once completed, don't return to the research group. Take the opportunity now to find research groups within your institution that are nicer and more willing to host a student because it sounds like the current group sees students as a hindrance rather than as a collaborator or colleague.

There are avenues you can take to make complaints about bullying in the workplace, such as speaking to professors (not unless they're the one involved in bullying) or going to a human resources division. However, this may not be in your best interests to do anything 'formal' at this stage of your career given you aren't committed to this lab group on a fixed term contract as an official job. I would be talking to the student mentor you mentioned in the comment about your experience.