Dropping out in second year to Restart

How exactly do you 'know you would get in'?
Which degree subject is this for?

Biomedical engineering. It has a high acceptance rate and I got in last year. But couldn’t go do to other reasons. Im confident in me getting the offer but if not I will have KCL as my insurance also for Biomed eng.

Just be aware that Unis are not enthusiastic about 'drop-outs' from other Unis, and may not be keen for a 2nd year to restart another degree. You will need to declare the QMUL study - and provide a detailed grade transcript. You might like to phone/email KCL first and ask them if they would actually be interested in your application for Year 1 after 2 years somewhere else. And SFE will only grant 1 extra year - not 2. You seem to be assuming quite a lot here.

Why are you worried about what other people think.

I currently go to QMUL. But I never wanted to go there and I hate it. Its been a year since I started and still can’t get it out of my head.
I want to drop out in second year and reapply to UCL (I know I will get in). I would be restarting from 1st year.
Sfe is sorted so don’t have to worry about that.
I want peoples advice on this and if its the right choice. I will technically be 2 years behind and will be 20 years old when starting again.

Just be aware that Unis are not enthusiastic about 'drop-outs' from other Unis, and may not be keen for a 2nd year to restart another degree. You will need to declare the QMUL study - and provide a detailed grade transcript. You might like to phone/email KCL first and ask them if they would actually be interested in your application for Year 1 after 2 years somewhere else. And SFE will only grant 1 extra year - not 2. You seem to be assuming quite a lot here.