To edit the Popular Courses section, you can edit the homepage then edit the widget Thim: Courses.

To remove the instructor name from this section, you need to add CSS in Dashboard => Appearance => Customize => General => Custom CSS & JS => Custom CSS

CSS to remove instructor name:

.course-item .course-author{
        display: none !important;
}

CSS to remove the number of enrolled students and comments:

.course-meta .course-students, .course-meta .course-comments-count{
        display: none !important;
}

CSS to remove the price of the courses:

.course-meta .course-price{
        display: none !important;
}

CSS to remove the “Read more” button when hovering:

.course-thumbnail .course-readmore{
        display: none !important;
}