1. Open your Google Admin console.
2. Go to Users.
3. Select the organizational unit to which you want to add the user. At the top of the page, click Add new user.
4. Add account information (visible in the Admin console and Gmail contacts):

Create a password:
Note: ​If you generate a password, it will be longer than the required minimum or the minimum password length set for your domain. (Optional) Ask the user to change this password the next time they sign in.

Click Add new user.

Note: If the new account's primary email address matches an existing Google Account, you might be prompted to fix the conflict before you can add the user. Learn more about conflicting accounts. (Optional) To paste the password somewhere, such as in a Google Chat conversation with the user, click Click to copy password. (Optional) To send account information to the user, click Email user sign-in info. If you entered a secondary email address for the new user, it appears automatically in the Email field. Use the secondary email, or update it to another email, then click Send to send the new user their login info.

You can add up to 30 aliases for each user, at no extra cost.

1. Open Admin Console
2. Go to Users.
3. In the Users list, find the user. If you need help, see Find a user account.
4. Click the user’s name to open their account page.
5. Click User information and then Alternate email addresses (email aliases).
6. Click Alternate email and enter an alternate username (the part of the address that appears before the @ sign). Note: You can't create an alias currently assigned to someone else, either as a primary address or alias.
7. Click Save.

(Optional) If multiple domains have been added in your Admin console, the field to the right of the @ sign is a menu listing available domains. Select a domain for the alias address. Note: Domains added as a domain alias don't appear in this list. A domain alias applies for everyone in your account and can't be customized for a single user.

Go to Apps > Google Workspace > Drive and Docs
Click Manage shared drives.
Point to a shared drive and click Manage members.
At the top, click Add people and groups and enter the names or email addresses of the people or groups you want to add.

(Optional) To change the access level of a user or remove them from the shared drive, next to the user, click the Down arrow "" and choose an option. Note: If you remove all members from a shared drive, the shared drive remains but is not accessible. To restore access to the files, add new members to the shared drive.

Tip: When adding multiple members, use Google Groups to make sure you Avoid exceeding limits