For food, you can try small of any of the ones you have for maybe small crickets. It’s gross the but the night crawlers you *can* cut to the size you need.. I’m sure pin heads would be too small if the flies are.
Here is a good care guide from the zoologist that used to be here. https://www.thecritterdepot.com/blogs/news/tomato-frog-care-guide
If you are using a heat and/or uv lamp always have a shaded area they can get out of the light available.
I’d say, with yours’ age, dust with the calcium powder every feeding, (after one yr go with the schedule in the guide above for all) , the multivitamin once a week, and the one with D3 once every one to two weeks. Really, as long as you dust multiple times a week with calcium, once a week with multivitamin and at least once a month with D3, it’d be ok.. You just don’t wanna get be too much D3 is the worry. Hope that helps!