SharePoint has Two Site Template Team site and Communication site. If you need to create the new site, you have the SharePoint admin permissions. You can go to Office.com
Select the SharePoint App in the top bar you can find the Create site link
Click on the link it will open the Create a Site page and show the two options of Team site and Communication site.
Team site:
Team site using for team collaboration, this is including List, libraries Pages and Subsite features. If you would like to create the company than you can choose the Team site template.
How to Create Sub Site
If you create a new SharePoint site that is called Top-Level site, here you can create the many sub sites. Following steps guide you how you can create the SharePoint sub sites:
1. Open the SharePoint site and go to Settings -> Site contents
2. Here you click on the New -> Subsite
3. In the Title you have to enter the Subsite Name
4. In the Web Site Address also enter the site name
5. Then select the language and template
6. If you would like to create the Team template, then you have to select the Team site (no Office 365 group) under the Collaboration Tab
7. In the user permission select the use same permission as parent site, if you would like to provide different user permission then select Use unique permissions
8. In the navigation section you have to select the navigation display and click to create the new Subsite.
9. Now new Subsite has been created in the SharePoint and the subsite link will be displayed on the top bar navigation. You can also follow the same steps to create the multiple subsite.