Night Crawlers cut to appropriated size is the best staple food with crickets, dubia or similar roaches, horned worms ( appropriate sized ) , pac food are all good for variety and treats...

check out this video and the others they may help.

Tong Feeding 101 - YouTube

also post some pics of the frog and its setup .. may help use spot some think before it becomes an issue...

BTW.... Welcome to the addiction!!!