Here is a learning support on using pronouns with gerunds. This is a half-page reading from Paul Brians’ excellent book Common Errors in English Usage, which you’ll find available to you, at no cost, under that hyperlink.
If you find typos in this document, I would appreciate a notification. And, as always, if you find this material useful in your practice, I would be grateful to hear what you think of it. I seek your peer review.