AMP for WP JavaScript, stylesheet Validation fix issue

im using Ampforwp, and i need to fix some issues like :
The mandatory attribute is missing in tag ‘html’.
Custom JavaScript is not allowed.
The mandatory attribute ‘amp-custom’ is missing in tag ‘style amp-custom’.
The attribute ‘href’ in tag ‘link rel=stylesheet for fonts’
The parent tag of tag ‘link rel=stylesheet for fonts’ is ‘body’, but it can only be ‘head’.