No Luke 3:23 has nothing to do with adoption or inheritance, the age of 30 (even 25 and 20 for probationary service) is when a Israylite is fully ready to be a priest;
Luke 3:23, "And when יהושע Himself began, He was about thirty years of age, being, as reckoned by law, son of Yosĕph, of Ěli,"
Numbers 4:23, "“Register them, from thirty years old and above, even to fifty years old, all who enter to perform the service, to do the service in the Tent of Appointment."
Numbers 4:30, "“Register them, from thirty years old and above, even to fifty years old, all who enter the service to do the work of the Tent of Appointment."
Numbers 4:35, "from thirty years old and above, even to fifty years old, all who entered the service for work in the Tent of Appointment."