How to put one video on top of the other?

While there is a message saying it solved, I'll just add a bit for others who may look at the post. 
Following what Peru Bob said, your tracks are your layers and what ever is higher in that order (more to the top) will appear above what is below. If you want to show 2 clips at the same time, you should scale the clips so they can fit next to each other within the frame size.
Below is a short video that demostrates this, using the same clip but displayed multiple times, using diffeernt tracks:
https://www.youtube.com/watch?v=xqgAGy6m9gE 

Videos on a higher track will be above videos on a lower track.

solved thanks