Hello everyone!

Soon, im going to get some Green Tree frogs and i don't want to spend money on buying crickets every week, so im going to breed them.

So, i have some questions.
From birth, how long do crickets live for?
At what age do they start to lay eggs?
Will they lay eggs without any substrate?

Thanks guys! Any tips and tricks you have will be great. Id love to know how you do breed them.