If you have full access permission in a Shared Drive, you can add individual users to a Shared Drive, or all members of a Google Group. When you add members, they will have instant access to all content in the Shared Drive.
To add an individual user to a Shared Drive:
Navigate to the Shared Drive you wish to add people to
Click on number of people in the Shared Drive, under the name of the Shared Drive
Click in the Add people and groups box and type the name or email address of the person you wish to add - you can add multiple names if required
Enter an optional Message to send to the new Shared Drive users
By default, each member that you add will be given Content Manager access to the Shared Drive, which means that they will be able to upload, edit and delete files in the Shared Drive, and add new members. To change the access of the member, click on the Content Manager drop-down arrow and choose the type of access you wish to assign to the user.
Click on Send
The following permission levels can be set in a Shared Drive:
If you don’t want to send an email confirmation to the new Shared Drive user, you can check the Skip sending notification option, then click on Add to add the new member.