MIGRATION with SDP AND OTHER QUERIES

Hi all and thank you for taking the time to read and hopefully answer my queries.

I am located in Scotland and receiving ESA with the tax code ESA500.
I am in the support group (I think, no requirement to seek work or attend activities) and I receive the SDP premium with the award.

I will make my migration to universal credit next week and have a few questions?

First of all my SDP was previously removed when a family member had to give up work and care for me after a severe downturn in health. This individual does not live in my household. It is a grown adult child of mine.

My SDP was awarded back after the individual give up the role of carer and carers allowance.

I know nothing about universal credit and how it works and am a bit terrified after lots of horror stories.

So, what happens if I ever get to that point of needing really intense care again?
Is someone allowed to claim carers allowance if I'm on universal credit and no longer on ESA?

What happens to my total overall award in all the elements (think it will be new esa, income related esa top-up and universal credit with housing benefit? if I am interpretating the code ESA500 correctly?

Is my monthly total reduced and if so by how much?
It was previously the value of SDP but I am being told SDP doesn't exist and something about I'll go through with a protected transition element and then 'other' elements.
So how much do I lose if someone has to claim carers allowance in the future?
Does it then work like SDP and the monthly award goes back up when they no longer claim?

I'm sorry if this a stupid question but I can't find an answer and I'm scared it isn't possible or will leave me in a heavy loss and maybe not affordable.

I have so many questions swirling round in my head. Is it ok if I start here then come back with more or is there a limit to the number of questions we can ask?

Thank you all so much.