As you say it is under warranty, that course is the best.
How successful you will be with the jammed keyboard USB - I am unsure, but you will not know until you try
You do not list what you have tried
1. Is to check the AC adaper if it is NOT clicked in place, then it may produce the problem you have
2. How to reset battery in Acer Nitro 5 model :AN515-55 ?? - Acer Community
3. If those methods do not work, rather than attempting any dismantling I strongly recommend the referral under warranty
How successful you will be with the jammed keyboard USB - I am unsure, but you will not know until you try
You do not list what you have tried
1. Is to check the AC adaper if it is NOT clicked in place, then it may produce the problem you have
2. How to reset battery in Acer Nitro 5 model :AN515-55 ?? - Acer Community
3. If those methods do not work, rather than attempting any dismantling I strongly recommend the referral under warranty