The first thing you'll have to do is to head over the Uber Figma Community and create a clone of the Base Gallery.Go to Figma Community
Click on the "Base Gallery", and hit "Duplicate" so you can get your copy of the Base Gallery. As the file is rather big, this may take a while.
Once the duplication is done, you'll be presented with an instance gallery of all the components that you can duplicate to drafts or publish as a team library if you have a professional team account. For now, the library itself is not published.
Figma Community enables design teams to share their work, and others to re-use them. You can learn more about it in the official announcement.
If you are new to Figma, check out the resources below: