how to connect drop down list with button and php file with if statement

I'm new in php, and I need help. I have created drop down list, than I should hit submit button and it should run one of my php files that are in drop down list. (using if statement) I tried in this way:

`

What Genre you want? Select... FPS JRPG RPG Sports

<?php if (Genre == "FPS"): ?>    

<FORM METHOD="LINK" ACTION="FPS.php">
<INPUT TYPE="submit" VALUE="Submit">
</FORM>;

</p>`