What can I earn

If anyone can answer this I would appreciate it.
Both my partner and I have been classified as LCWRA, I am carer to my partner who has an ongoing health issue that will not be improving. We have a joint UC claim and both get pip, me only lower daily living, her, lower living, higher mobility even though the court awarded her higher rate on both but that’s a different story! We claim carers allowance as well as I’m looking after her.
We are really struggling and I’ve been offered some driving work delivering parcels, 1 or 2 a day but over distance! (The ideal job for me with pain and mental health issues) but I’m finding it impossible to find out how much I can earn before losing benefits! Basically I can choose my hours with this job so that’s a positive but I can’t afford to take work and lose money! And from what I can work out if I work 5 days a week (I can’t as I need to look after my partner) we will be 96 quid a month worse off!I tried to ask the DWP but was threatened with investigation and all sorts causing me a major panic attack. The figures that I’ve found only appear to allow me to work less than 1 day a week! Can anybody explain how working on UC works please? It appears I can’t even work a whole day a week from the figures I’m seeing,
I desperately want to do some work and increase our income as we are struggling but I can’t risk our benefits either! Please help!

Yes I’ve tried that but it’s insanely confusing! Yea we get carers allowance and I’m aware that it’s not much before you lose that from what we were told! I’ve tried the so called benefits calculators and all that does is tell us what benefits we can get! I know that as we get them! I’m concerned that we will end up worse off! I can’t do more than maybe 1 or 2 days a week anyway but even that seems like it will cost us!