Hi Adnan,
Looks like you're missing the xml namespace for the Matrix Layout tags.
On your first line include the following -
xmlns:l="sap.ui.commons.layout"
Then when you add the XML tags for MatrixLayout and related elements in the body of your view make sure you use the correct namespace
<l:MatrixLayout>
<l:MatrixLayoutRow>
etc. etc.
Refer to the MatrixLayout in the SAPUI5 API - MatrixLayout for more information.
The SAPUI5 developer guide also has some great Tutorials and the Explored section provides good examples with code.
Cheers,
Stephen