Help needed A1 How to change g-code to start height

hej, my printer is an A1 (not mini)
I hope X1 g-code is the same.

the g-code files from my old printer start printing in the air, just a few 0.1mm above the plate.

is it possible to find and change the Z-height in the code?
/Lena

ps. the original 3d models are lost :sob: