I'm not in academia, but, FWIW:

Read the conference guidelines. Read old proceedings. That tells you how to submit and what has been accepted. Every conference is different, and has a different style, etc. Know your competition.

A paper is always better than a poster. A poster is better than no poster.

Getting advice from one of your profs is a good idea (and could be a potential co-author). Being second author on a paper is usually better than a poster.

Being first author is better, but harder (unless there's a student section). Having co-authors is pretty much the norm for papers in some fields. (See "Read ... ," above .)

Please post a link to the conference!