There are a lot of errors and bad tag formatting in your code. Tags should also not overlap (first open, last closed), like in the following part of your code:
</div>
</button></h2>
</div></div></body></form></button>
This not valid formatting.
Each tag has a specific use, for example:
<h2> tags are used to define second HTML headings of a page.
They should not contain anything else than the title of the section they define.
The closing body tag </body> can’t be followed be any by anything except </html> tag.
You should probably rewrite the whole thing.