Microsoft has secure AI tools you can embed into word, if you have the right licensing, and there are proof reading add-ons. If in doubt check with your university.
Would your essay get cached publicly? I think probably not, but i am not certain and with the risk of academic misconduct being significantly more serious then the relatively modest amount of time you would save using chatGPT as a proof reading service it’s probably not worth it imo.
More importantly, university is about education & self improvement, you will develop more personally holding yourself to the highest standards regardless of grades for the eye for detail you hold to any report you put your name on in the future.