I think this can be done with a GroupSelector field and setting "group can modify" etc on the tracker permission properties - as with "user" owner fields you need to set the perms on the tracker so the groups you want can create new items, then they only can see or modify them.
Vincent, this also could be part of solution (group fields I mentioned = GroupSelector field) but be aware that editing has "admin" can have harmful results on an item where the "modifier" or "creator" are auto-assigned.
Recently I experiment this field in combination with user tracker registration and I almost locked my admin user out of the system changing a usergroup as I was logged as admin. (Hi Jonny 😂 )
I kindly suggest before you polay with this you create a second admin with a different name and good password (of course) for safeties and you use a "super user" or the real user you target to test the behaviour (but mot admin).