Custom Crops Help

I tried following NorthWestTree tutorial but it's too difficult and some of the blocks aren't here.

I have made all stages, seeds, food.

I already made the script of checking if the block below is farmland.

Here is it :

==the event is when you click farmland==

Event trigger : None

if main hand OR off hand is equipped with custom seed AND block click = farmland

AND that the block up the farmland is air THEN

remove air

place level 1 tomato crop

if player/entity not in creative then

remove 1 tomato seed from inventory

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when destroyed by explosion

it drops tomato seed

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if grass or fern destroyed

(not grass block)

drop custom seed

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what im searching is to grow on water close OR rain

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