Part time work varying hours, will I be worse off?

[WhatToDoHmmm]

Hi everyone.

I'm a single mum, my sons dad is not part of his life. I've recently started a new job, the hours are up and down (8-18). I won't be entitled to child care (I have a 5 year old).

Will working such random hours effect my child tax credits/ universal credits/housing benefit?

I'm not really sure how this all works, I was informed the first £80 I earn is mine, then after that it effect my money. I'm now worrying I'm going to be worse off with the hours being inconsistent.

Yeah, the more you earn the less UC you’ll get. For every £1 you get in wages you’ll lose 63p of UC so you should still be financially better off going to work.
You can still get the childcare element of UC for primary aged children. You will just need to plan, so if you’ve done more hours you’ll know the wage due will be higher and therefore your UC payment will be lower.
Your job coach/journal is best placed to give advice to your specific circumstances.