>>7619165OP, you need to think very carefully, what's the worst possible piece of evidence they could have found of you cheating. Not the most likely evidence; assume they found the most incriminating thing about whatever you have done.
It doesn't matter on what portion of the work you cheated; any cheating is an extremely serious offense because it automatically calls into question your trustworthiness on the rest of your work, and letting you get away with it sets an unacceptable precedent.
Virtually the only possible way it could "not be that bad" is if the cheating was beyond reasonable doubt due to some misunderstanding rather than a deliberate transgression. Whatever excuse sounds reasonable to you, however, may not at all to a professor that may have experience with this sort of thing.
If you think there's any possibility they have some incriminating evidence against you, and they've given you the opportunity to come forward, I would do that and plead utter ignorance and stupidity. You may be fucked for a long time having that on your record but at least you won't be expelled and barred from university in the foreseeable future.
If you choose to deny, then get your story straight, consider all contingencies, all pieces of evidence they might ask about, and stick to it no matter what; don't make up shit as you go, just act natural and deny no matter what..
