Team templates are pre-built definitions of a team's structure designed around a business need or project. You can create your own template in the admin console. With Microsoft Graph, you use the pre-built templates.
https://lettstartdesign.com/category/premium-admin-bootstrap-templates
https://lettstartdesign.com/category/admin-dashboard-template
https://lettstartdesign.com/category/bootstrap-templates
https://lettstartdesign.com/category/landing-pages-templates
https://lettstartdesign.com/category/business-corporate-templates
https://lettstartdesign.com/category/portfolio-resume-templates
https://lettstartdesign.com/category/angular-templates
https://lettstartdesign.com/category/freebies
https://lettstartdesign.com/theme/agency-landing-pages
https://lettstartdesign.com/theme/creative-landing-page-templates
In the channels, tabs, and apps section, add any channels and apps that your team needs.
In the Channels section, select Add.
In the Add dialog, name the channel.
Add a description.
Decide if the channel should be shown by default.
Search for an app name that you want to add to the channel.
Select Apply when finished.