Sorry but this kind of image manipulation is not within Lightroom's goal and more oriented toward Photoshop and similar image composition editors.
Please check the below links to know about image overlay in Photoshop:
For more result kindly check the google search.
Google search: Google
Thank you for the reply. I just purchased this today directly from Adobe. The sales lady told me this is what I needed to do what I was talking about. Are you saying there is something else?
Lightroom is not the tool to do this. Photoshop is the tool (or Photoshop Elements).
Do not be confused by Adobe's poor choice of names, the official name of Lightroom is Adobe Photoshop Lightroom, which is what you have, and this is different from Adobe Photoshop, which is what you want.
Overlaying one image on top of the other is a task for Photoshop or Photoshop Elements (a more user friendly version of Photoshop with fewer tools and capabilities). If you are only doing such projects, you should look to purchase Photoshop CC (a subscription only ) or Photoshop Elements (a stand alone product). However if you are using Lightroom AND would like to use Photoshop, the best is to get the Photographer's bundle subscription - which is basically $10 US a month and you get all the power of both applications plus more. You can start in Lightroom, select a photo, ask it to edit in Photoshop, which then automatically opens photoshop. When you save from Photoshop after doing a bunch of manipulations including overlaying one image onto another, it saves the completed image back into Lightroom so you can keep it organized! And - not to sound like a sales person which I am not! - the $10 a month also gets you 20 GB of online storage free and best of all, access to some tutorials that are not generally available. Those tutorials are well worth the time to watch !