Definitely tempted to try something like YNAB. I need to be able to see, in some way, how much is left
Another way, that's free and less faffy once set up, would be to set up standing orders to different accounts. Or pots within the same account.
One for mortgage/rent and other regular bills
One for food/petrol/transport and other day to day essentials
One for annual and irregular expenses like Christmas/holidays/insurance/car repairs, white goods replacement, vets bills, school uniforms etc etc etc
One for car replacement, home improvements, other big expenses
One for genuine emergencies like loss of income due to illness/job loss etc. Maybe combine this and the other two in one account, but three pots if you want to.
What's left can be split for family days out and then separate accounts for personal spending for adults. So you have a 'family days out' pot so you know how much is affordable for all of these.
Once set up, you just need to check once a month that all is well and maybe adjust the standing orders if you've built up too much of a surplus (eg not had holidays due to covid, saved enough to replace all your appliances but everything still works, that sort of thing) or had to overspend due to a larger than expected car repair bill.
For getting more for your money for days out, always look for a deal or discount code, they're nearly always available and, like a PP says, take a picnic from home as a default. Food at attractions is almost always overpriced, poor quality and at the end of a long queue. Why would you want to eat it anyway?