No, there is a single call that adds members to a group as shown below.
PATCH https://graph.microsoft.com/v1.0/groups/{group-id}
{
"members@odata.bind": [
"https://graph.microsoft.com/v1.0/directoryObjects/{id}",
"https://graph.microsoft.com/v1.0/directoryObjects/{id}",
"https://graph.microsoft.com/v1.0/directoryObjects/{id}"
]
}
You can check this documentation
If you want to add the same users to different group, you can use a for loop and use this call by changing the group id.
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