anonymous user Thanks for reaching out.
If it is a task of just adding members, you can assign a role of Group Administrator to user who is responsible for managing groups.

Do remember this Group administrator role has following limitations :
1) The role is designed mainly for Office 365 groups and cannot manage other group types like distribution groups, mail-enabled security groups or shared mailboxes.
2) This role cannot be used to update a Group’s email address or modify external mail or mail delivery options in the Microsoft 365 admin center.
3) You cannot use Exchange PowerShell cmdlets to manage Office 365 Groups.
4) A Groups admin cannot manage audit logs, access reports, or guest settings.
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