Create overrides for admin/com_jem

Greetings,
I edited the first custom field in administrator/components/com_jem/models/forms/ adding " filter="safehtml"" so I can use a link.
How do I prevent this file from being overwritten on update?
Or is there a better way to make this change?

Thanks

Please make an override:
docs.joomla.org/J4.x:Template_Overrides

Thanks.

I didn't know that applied to administrator/component/com_jem files.
What's the difference between /administrator/components/com_xyz and /components/com_xyz

/administrator/components/ is for the backend
/components/com_xyz is for the frontend

I want to protect this file from updates:
/administrator/components/com_jem/models/forms/
because I have added a field to custom1
it was overwritten by the update from JEM 4.0 to JEM 4.1.0

as much as I know it is not possible to create a template override for that!