Hello and welcome to the forum. Unfortunately your pictures are only thumbnails which makes an ID difficult. Perhaps you can try again.
From what I can see I believe that you have purchased a Chinese Elm. If you search the forum you will find more than a few threads about this species.
Check this thread for some basic tips especially concerning watering.
Other than that, in the short term, ensure you have drainage holes in the pot and that the tree gets adequate light. Don't rush into anything until you do some basic research.