You can remove featured image from portfolio page by using following custom CSS code.

.single-fw-portfolio .sh-portfolio-single-image {
    display: none;
}

The portfolio page doesn’t display titled gallery. You can either add jetpack tiled gallery in the content of portfolio page or develop custom code to achieve this.

Developing custom code for custom functionality is beyond the scope of support that we provide here.

If you are not a developer then you can consider hiring a developer to develop it for you. You can hire a developer from any freelance site. Shufflehound recommends the developer https://www.upwork.com/freelancers/~011652ffec8865c6d5