To get started with Android/TenX-OS, you'll need to get familiar with Source Control Tools.
To initialize your local repository using the TenX-OS trees, use a command like this:
repo init -u https://github.com/TenX-OS/manifest.git -b fourteen --git-lfs
Then to sync up:
repo sync
Please see the LineageOS Wiki for building instructions, by device.