git clone <server.repository>
git submodule update --init
If you want to make changes in a submodule or update to newest submodule also execute:
git submodule foreach "git checkout main && git pull"
Make sure to commit submodules first!
Also make sure to push submodules as well.
Create a new repository with name server.<repository>. Then go to the project folder and execute
git submodule add -b main https://github.com/Vereine-Vereint/server.core.git core