Can I send the first draft of the paper to my roommate?
You can't. If the first draft and the second draft come, there is no problem, but it is still not recommended to show them to others. Because a professional paper may have some similarities, even if the other party doesn't intentionally copy your paper, if you subconsciously write down some arguments and apply them to your own paper, your repetition rate may increase and plagiarism will occur.