Try putting your requirements (date, party size, departure airports) into the deals section of [[https://www.jet2holidays.com/?ds_rl=1206481&gclid=Cj0KCQjw7YblBRDFARIsAKkK-dLWTb4X5JP-SdnwRXic3fOqiIiqNdf2W6ikKsIPV78Sod6_hOX6k64aAtzyEALw_wcB&gclsrc=aw.ds Jet2holidays. You can then sort by price to see if there is anything suitable for your budget.
Somewhere like the Costa del Sol might suit as there are museums in Malaga, a trip into the mountains is an option, plus beach, pool etc. However, it will be very hot in August. Northern Spain might be a better option - Costa Brava or Dorada. Or there's mountains and museums in Tenerife and Lanzarote and it shouldn't be as hot.
I would go self catering or B&B in an apart hotel, so then you're not tied to the hotel for food and don't have to worry about it not being to your taste. You can eat out once a day and then have easy food in the accomodation, pizza, barbecue, bread, cheese, ham, olives, crisps, etc.
I wouldn't take much notice of what others spend. Some have extremely exacting requirements and the budget to service it. Others seem to find an unbelievable amount of holiday for an impossibly small budget. I would like to see the latter in action, because I'm not sure if some of the claims can actually be turned into reality tbh.