Auto fill some custom module fields from a Account lookup field

Auto fill some custom module fields from a Account lookup field

Hi,

I created a custom module linked by a lookup field to the Account module.
I have created some new fields in this custom module, similar to the Adress, City, and Zip code fields, existing in the account module.

Now, in the Custom Module, When I select the account name in the lookup field, I would like the address, postal code and city fields to be filled automatically from the Account module data.

I do not know how to write this script. Can I have an example? I can't find something on the forum.

Thank you for your help

Best regards,

Jean