If you need to clone a project within the Pantheon ecosystem Terminus is a great tool to use.
After authenticating with terminus use the site:clone command
terminus site:clone <source>.<env> <destination>.<env>
<source> and <destination> are either the site names or the site UUIDs. <env> is the environment, e.g. dev, test, prod or multi dev.
- Install Terminus
- Terminus's Site Clone Plugin
- Terminus Documentation
- Pantheon Migration Documentation