From either browser or file explorer, right click on the file/folder and select “Share” from the pop up box.
You can choose to share access to a file/folder via link or via email. Clicking on the arrow beside “Anyone with the link can edit” in the screenshot above will open a dropdown menu where you can select either option.
Choosing the link option means that anyone who has the link will be able to access what has been shared.
Choosing the email option will restrict access to only the people that explicitly have permission to the file/folder.