Esa contribution support group

I really need some advice please
I'm on Esa (C) also enhanced pip on both which pip is up for renewal!

My husband earns about roughly £30000 pa

What concerns me, I do not want to claim UC if and when ESA (C) migrates over , ive over 35yrs NI paid in , so therefore if I don't claim Uc how do I pay a stamp ! Also if I don't pay a stamp for several years in a row would I be able to put in for a claim for benefits say 4yrs down the line !!!!
Or the other situation is my husband earns to much and i wont be entitled to anything ! So therefore my stamp won't be paid ! Would I still be entitled to my state pension /benefits if no stamp paid for the next 4yrs !

Thank you for any advice given

Still on ESA[C]. If relative's [she's in support group, get max PIP] husband has to give up work due to getting cancer, and needs to claim the appropriate benefit [ESA? UC?] will this affect the wife's ESA[C] please? I understand that couples' incomes are jointly assessed for UC? And I know you can't return to legacy benefits.
Thanks

Thank you Gary. As I feared, far from straightforward. Regrettably the advice centre found via the link has a bad track record with one of us, so it would not be easy to trust them again. We did have good help ten years ago from another organisation, for carers, that isn't listed on advicelocal. I'll see if they can help again with the differing circumstances.
The caring is more likely to be wife, though disabled herself, caring for him as his severe dyslexia etc means she already organises all his life admin and medical stuff, which there's now much more of. If they can manage without a carers element that might be best, to avoid a risky challenge over her PIP at review. long sigh...Thanks again.