How to pass code validation?

Question

HTML

Please take a look: https://validator.w3.org/nu/?doc=http%3A%2F%2Fmult...

I don't understand at all how to solve the 2nd and 3rd error, as in the screenshot - please help.

Answer 1

It's all there -_-

Answer 2

2. It is recommended to use a heading of a different level, perhaps this is the second h1 on the page, double-check that there is only one heading of the first level on the page.
3. section element must contain a h2-h6 child element, otherwise it's better to replace it with div
In general, this is a warning, not an error!