Looking for a sharing platform

Hello! I am trying to find the best sharing platform for my organization.

I have a doubt about the plans and the possibility to interact. If I buy the PLAN 1 Subscription for one user, is it possible for other free accounts to interact with Sharepoint?

To be clear, I was wondering if it can be used as Google Drive, where there could be one premium storage account with a subscription and infinite free editors and users with their free gmail account.