1. Go to Google Drive (drive.google.com)...
2. Choose Shared drives on the left.
3. Right-click on the shared drive you want to manage access. Click Manage members.
4. In the newly opened window enter the Google Group, the members you want to grant an access. Then click on the blue Send button. (In case you don't have any Google Groups - go to 4.1 - 4.4 paragraphs). Find more in this article.
4.1 Go to the Google Groups (groups.google.com)...
4.2 Click on the Create group button on the left upper corner.
4.3 Set up everything needed.
4.4 Add members. Then click on the Create group button.