New too toon boom with animation-ish problem

Hi anyone…
I have created a photoshop image (as my drawing skills are lacking, I tried drawing it in animationish but looked terrible.) and what I want to do is quite simple, I thought animationish would do this for me. Have a look at attachement.
this is what I want to do:

part one green grass only (not growing, just there)
part two poppies grow, flower heads appear
par three title appear one letter at a time.

This is a promo backdrop for a school play so i will eventually export to .mov. and display thru a data projector.

Very new to all this
But can use photoshop, premiere elements and obvious a bit of animationish. But not much. Have done the basics.

I think I want to create a flip book ish but I dont want to draw it as I cant as well as i can use photoshop.I cant import into flipbook. And I cant seems to erase the bits (in reverse) in advanced ish.

Any ideas?

Animationish is simple product for K-12 drawing frame by frame expressing the animation. There is automatic inbetweening. Also when bitmap image is imported, it is vectorized as texture that you can either transform or use eraser to erase but nothing more than that.