I have been a single parent for 2 years now to three children agreed 6-13. I had taken an 8 year career break (I previously had a well paid career) and had just started a job in a school a few months before the split. It was very low hours and term time only so paid barely anything, it just about covered youngest's nursery fees.
When we split, I claimed universal credit which then covered 85% of the childcare fees, child maintenance (rate ex paid was based on the government website calculation), I then had my wages and chil benefit. With those combined I was able to cover the mortgage and all bills for the house and the children's expenses. It was tight but I managed it.
I have gradually increased my hours at work, and have been retraining at college on my days off in the hope of being able to build a new career. My childcare costs are lower now that I'm just paying for breakfast club and a Childminder for a few hours a week. It does help working term time only so I don't have to worry about childcare, but the trade off is a lower wage.
If you are claiming universal credit you can claim back 85% of childcare costs for holiday clubs during the school holidays if the provider is ofsted registered. My kids love holiday clubs and would happily go everyday if I was workinh during the holidays.
Did you have a field of work that you were in previously that you could easily go back to? Do you rent or have a mortgage (universal credit will help with rental costs but not mortgage). If you aren't already claiming universal credit do check the entitled to website to see what you can claim. I would suggest applying for everything you can, my children were eligible for free school meals, I got council tax support, the cost of living payments this year, warm homes discount towards energy bills and a slightly reduced tarrif with my water company. As my income has gone up the help has decreased, but it was really needed in the beginning and such a huge help.
I will never forget ringing the council tax team to remove my ex from the bill in the first few weeks and the lady on the phone told me 'just remember how strong you are, you can do this on your own'. I desperately needed to hear it that day and I often think of those words when I am having a tough day. Please remember you are strong and can do this. It is tough trying to juggle work, childcare, the kids, studying, etc. but you can and will do it and you will set a wonderful example for your children.