Are you at a public or private school?

If it's a public school, as long as you make a good impression, admit what you did, and seem to show contrition, you'll most likely get to say in school. Unfortunately, the F is almost definitely going to stay on your record. You'd have to talk to advising and ask if it will be reflected on your transcript. Some schools give notes on the transcript as to why the F was received. At my school, a professor would sometimes give an FX or an FW instead of an F, which stood for "extenuating circumstances" or "late withdrawal." There may be a "disciplinary" notation or something at your school that the professor could use to notate the reason for the F if she so chooses. You may also have the option to retake the class and have the F scrubbed from your record if you get a C or better in your second attempt.

If you go to a private school, especially if it's religious, conservative, and/or highly competitive, you might be in quite a bit of hot water. It really depends on how the administration of your particular school tends to deal with these kinds of charges. Look up academic dishonesty in your school's catalog and see what the usual process is. Also try talking to advising and see if there's a student union of student organization that might help you prepare. If you can obtain some kind of representation, do this before you do anything else, and listen closely to their advice.

If you are unable to obtain some kind of representation, then I recommend you see if the professor which brought you up on charges will consider meeting with you. Explain your side of the story, but don't lie or insult her intelligence. You were in the wrong to do what you did, whatever the reason, and you deserve an F. Ask her if there is anything you can do to avoid getting kicked out of school. If she believes you're really sorry, that you learned from this experience, and that you're not likely to repeat it, she may be willing to speak on your behalf at the hearing and recommend you be allowed to stay in school. She may even be willing to withdraw the charge and just give you an F, if she can.

I would recommend e-mailing first and asking if she'll meet with you. If she says no, accept it and do not argue or make things worse. Do not risk showing up to her office hours unannounced.

Good luck.