you need a really big container with lots of different niches. don't get toxic ones. turtles will eat the frogs. most lizards need a very hot environment. not so much for the frogs and turtles. so primarily don't do it.
I own 3 turtles all red eared sliders. The two babies that have been raise together get along fine. The oldest however has never let anything live within his tank and I mean anything. I've tried everything fish (including an algae eater which he didn't eat he a moment ago killed it. I assume trying to figure it out, turtles bite to figure out trial objects in their tank), crawdads, frogs,and tadpoles. As for the lizards I don't think they'd do so hot. A newt would be a little better suited for indistinguishable environment with a turtle, but they produce toxins in their skin which might make the other reservoir inhabitants sick. Anything that goes in the tank near a turtle runs the risk of becoming lunch. I've had fish that lasted 3 years, but most don't clear it a week.
Ideally to have this habitat you'd have to have a massive cistern with lots of different water and land areas, the more room the creatures have to avoid each other the better.
Answers: no there are loads of reason why and dangers (btw never mix turtles near lizards or frogs as they are natural turlte food)
main issues are
fighting/eating one another
all animals inhabit neiches and enjoy specific care and its almost impossible to replcate these in a container
spreading/incompatable disease,bacteria,parasites or toxins
more in depth
there are no small aquatic turtles that can live beside what you want...they are canabalistic and will kill their own kind for space and food.
Total Body length: 5-8" average for males, up to 12 inches max for females. Life span: 15-25+ years
Males have the longer front nail and are used in mating. And are considered mature at going on for 5 yrs old. You can’t start sexing till about 3” across.
Depends on what kind of frogs/lizards/turtles you're talking in the order of. Some lizards might eat the frogs and remember, turtles(and some lizards) will GROW and get big. You should do some research about specific types you're interested surrounded by and who they can be housed with and at what temp/humidity. Also look into what, if any, illnesses/parasites they can transfer to respectively other. You don't want them to get sick.
no the frogs will be eaten.They have different environments.