Yeah, keep photography as a hobby
Very, very few people are able to make a decent living from it professionally and it's very precarious. In your situation, with kids, I would not advise coming off benefits into such a precarious role with huge fluctuations in earnings.
Keep it as a hobby, take some courses in it for interest and give you a confidence boost but I'd really counsel against it - I know a lot of people with significant advantages over you (young, no kids, highly flexible, can travel at a moment's notice) and they struggled to live off photography earnings.
I also wouldn't worry too much now about what you want to do exactly. You need the English and maths and preferably science level 2 qualifications before anything else (normally) so get to your nearest FE college and start in September.
Once you are studying those, you can access careers advisors in the college to talk about long term options and there may well be a series of taster events learning about different roles. So if you start with the English and maths level 2 courses, you'll also be in the right place to start learning more about future options.
All work requires decent IT skills these days including nursing. I would suggest looking at getting your word processing and spreadsheet skills into shape..lots of useful online courses on word and Excel. Taking something the European computer driving licence (ECDL) would also be good. There are three levels but just getting the basic one done would be a start and help overcome future employer's concerns that having been out of work or education, you may not be familiar with modern IT.
You can do it at home as long as you have windows laptop or there will be computers to use at college if you don't.
It would also give you a confidence boost to get another qualifications and with your GCSEs in English, maths and science and ECDL, you may find employment options open up straight away.
Here is a site where you can test your IT skills
www.diagnosetest.ch/en/bestellen/