You cannot implement HTML this way.

You have to follow Magento 2 frontend architecture. https://devdocs.magento.com/guides/v2.3/frontend-dev-guide/bk-frontend-dev-guide.html

You have to knowledge to Layout and templates, Less, knockout Js,require JS.

You have used the basic way to include js to the system, You cannot add js at this way at magento2.

So,follow magento2 frontend architecture.

You cannot implement HTML this way.

You have to follow Magento 2 frontend architecture. https://devdocs.magento.com/guides/v2.3/frontend-dev-guide/bk-frontend-dev-guide.html

You have to knowledge of Layout and templates, Less, knockout Js,require JS.

You have used the basic way to include js to the system, You cannot add js at this way at magento2.

So, follow magento2 frontend architecture.