"Both are kept in same folder."

Sounds like you need to read about how CGI works. Tutorials provides a start; but don't stop (or maybe, don't start) there: you need to understand how Apache should be configured ... and why.

It's my suspicion (and only that, as I make no use of Tomcat) that the error message, "Servlet cgi is not available", is a red herring ...
    OR
that your install procedure went awry.

OTOH, your html is non-compliant; and your .cgi -- well, let's just say, it's -- um, almost, sorta' close but not quite right.