I have installed all the packages for miktex now. I re-ran my code with you told me and now it says <br><br>This is pdfTeX, Version 3.1415926-2.4-1.40.13 (MiKTeX 2.9 64-bit)
<p style="margin:0px;text-indent:0px">entering extended mode</p>
<p style="margin:0px;text-indent:0px">(C:\Users\azeem\Desktop\tutorial.tex</p>
<p style="margin:0px;text-indent:0px">! Undefined control sequence.</p>
<p style="margin:0px;text-indent:0px">l.1 \documentclass</p>
<p style="margin:0px;text-indent:0px">                  {article}</p>
<p style="margin:0px;text-indent:0px">? <br></p><p style="margin:0px;text-indent:0px"><br></p><p style="margin:0px;text-indent:0px">What shall I do now ?<br></p><br>