Question: If the nominee in a life insurance policy is a minor, can the policyholder appoint someone to receive the money until the minor turns major?
Answer: Yes. Section 39 allows the policyholder to appoint a person to receive the money during the minority of the nominee.

Supporting evidence:
title: noc.irdai.gov.in/Insurance%20Act,1938%20-%20incorporating%20all%20amendments%20till%2020212021-08-12.pdf
quote: Provided that, where any nominee is a minor, it shall be lawful for the policyholder to appoint any person in the manner laid down by the insurer, to receive the money secured by the policy in the event of his death during the minority of the nominee
context: icy of insurance under sub-section ( 1 ), the liability of the insurer shall be limited to the amount secured by partial assignment or transfer and such policyholder shall not be entitled to further assign or transfer the residual amount payable under the same policy.
39. Nomination by policyholder. -( 1 ) The holder of a policy of life insurance on his own life may, when effecting the policy or at any time before the policy matures for payment, nominate the person or persons to whom the money secured by the policy shall be paid in the event of his death:
Provided that, where any nominee is a minor, it shall be lawful for the policyholder to appoint any person in the manner laid down by the insurer, to receive the money secured by the policy in the event of his death during the minority of the nominee.
(2) Any such nomination in order to be effectual shall, unless it is incorporated in the text of the policy itself, be made by an endorsement on the policy communicated to the insurer and registered by him in the records relating to the policy and any such nomination may at any time before the policy matures for payment be cancelled or changed by an endorsement or a further endorsement or a will, as the case may be, but unless notice in writing of any such cancellation or change has been delivered to the insurer, the insurer shall not be liable for any payment under the policy made bona fide by him to a nominee mentioned in the text of the policy or registered in records of the insurer.
(3) The insurer shall furnish to the policyholder a written acknowledgement of having registered a nomination or a cancellation or change thereof, and may charge such fee as may be specified by regulations for registering such cancellation or change.
(4) A transfer or assignment of a policy made in accordance with section 38 shall automatically cancel a nomination:

ASSGNMENT OR TRANSFER OF POLICIES AND NOMINATIONS

Provided that the assignment of a policy to the insurer who bears the risk on the policy at the time of the assignment, in consideration of a loan granted by that insurer on the security of the policy within its surrender value, or its reassignment on repayment of the loan shall not cancel a nomination, but shall affect the rights of the nominee only to the extent of the insurer's interest in the policy:
Provided further that the transfer or assignment of a policy, whether wholly or in part, in consideration of a loan advanced by the transferee or assignee to the