advice repairing a jacket?

hey y’all! a bit of a random question but during a closet clean out i recently found a jacket that i bought about a year ago off depop which did not come in great condition haha. the main problem is that the inner material is ripped in multiple places and basically shedding little pieces everywhere making it pretty unwearable. i’d love to be able to repair it but i have no experience repairing clothes whatsoever, is this something that i can fix at all or is it a lost cause? it doesn’t matter what the fix would look like bc it’s on the inside, i was thinking of maybe trying to duct tape over it lmao but i have no clue!! any advice/random ideas are very appreciated