Hi Kenny,
1. Please add below code to Claue > Theme Option > General Layout > Custom CSS
.jas-portfolio .page-head {
display: none;
}
2. I’m sorry the portfolio not support Gutenberg, you can use gallery element of Elementor to build portfolio
3. Yes, the headẻ should be header layout-2.php
Please reply on this topic so we can track your issue and help you faster. I hard to read your email with more signature text.
Kind regards
Harry
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