Hello i'm making a modpack,
And i want to change recipes of the plane workbench

How can i do this?

Ok thanks!

Use any datapack mod which can replace normal recipes. Then you can replace the aircraft recipes just like the normal ones.
https://github.com/przemykomo/simple-planes/blob/master/src/main/resources/data/simpleplanes/recipes/helicopter.json here is an example helicopter recipe