My problem with the database.

Hi everybody. I'm currently developing a xamarin cross platform app but I have some troubles with database.
I have chosen ms sql server as database and I made the connection of the app with the system.data.sql referance but now I have to upload some pictures from my phone and display in several places.
I could not find enough resources and I have never worked with web api and could not understand it fully.
Can I upload my pictures by working with the web api ?
And can this web api make the connection with the local server that I'm using currently ?
Thanks for advance.