Improving and new features to my page

I am designing a little tool to identify organisms and is online here:

ID Tool Link

I have some features in mind which I need some assistance. The page is php / mysql. Maybe first we discuss if the page can be improved.

I don’t know if I should put the php or html code here apart the css?

Tell us what you’re trying to do, and what code you’ve already tried, and we’ll tell you if we need any more info.

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