You can create a space within your Community in the following steps:
1. Click on the Commerce tab on the left side bar.
2. Click on Community.
3. Click on the Community you want to add a space to.
4. To create a new space click on Settings button.
5. To add a space, click on Spaces on the left and then click on the Add Space button.
6. Name the Space, set permissions and add a description.
7. Hit Save.
8. Watch the video below for more information.