So sorry to hear your news. I hope all goes well in the end.
The other advice people have given you on this site is very good.
I just wanted to add that if you have a mortgage it's worthwhile contacting your bank for hardship help. Apparently they have this but don't advertise it. It's very hard having money worries while going through treatment.
Also centre link has a small carers pension available for people who care for someone very ill. I don't know much about it, ad it's not much, but might come in handy of you stop work and don't have sick pay,
Don't be too proud to ask for help. With little ones, and cancer, you need as much help as you can.
Everyone is different, but if you have to cut back on work, there is no shame in it. Chemo is very challenging for some of us. And oh the joy of chemo brain! There will be plenty of time to work when you are well again.
good luck with everything Karen