A group of Microsoft Products and technologies used for sharing and managing content, knowledge, and applications.
Hi Dubstir,
Here is the SharePoint Online planning guide which can help you learn more about SharePoint Online.
*Click the left pane in the article to view each section.
As for your question, it's suggested you build your Office 365/SharePoint Online environment based on your own needs (you can refer to your Intranet structure). But I'd like to share some personal ideas regarding "best practices".
- Please notice that Site collection is different from Sub site. They are under different levels.
Normally domain.sharepoint.com/sites/site1 means it's a site collection.
domain.sharepoint.com/site2 means it's a subsite.
- It's always suggested that you use the default top level site collection domain.sharepoint.com first. And use Team site for general sites.
To avoid making the site collection complicated/miscellaneous, you can set different site collections for different use, like departments, functions, etc. For each site collection, you can create subsites to add more contents.
- About how to choose Communication Site or a team site, please check the following. You can choose them based on their functions.
Create a team site in SharePoint Online
Create a communication site in SharePoint Online
Regards,
Jim