Please help me!!! Thank you every much!!!
1). Go To marketplace and then add your package or sample files or Project Demo to Your Vault.
2). Now Open Epic-Games Launcher under Library You can see your all stuff which is added from market place or in Learn Section.
3). Click add to project or Create Project.
4). Done Your Files will Download soon.
To add onto this, if you want to view the location of your vault cache on your computer you can click the settings icon and then click “Edit Vault Cache Location”