Hello. Can I somehow display Buy button on VirtueMart AMP product pages? By clicking on this button, the user needs to go to the normal product page.
There's no automated way to do that at this moment. A manual way is to include in the product description a link to that page. That link can be displayed only on AMP pages by wrapping it inside a specific tag:
See documentation on this page for more details.
You can also create a template override for virtuemart product page and automatically include the above in those overrides. That will require a little bit of programming.