Hii ,
I tried to creating a course and adding description from backend and it was clearly visible to front-end as well .
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To add space between instructor name add this code in apeearance >> Customize >> Custom CSS
.course.directory .course_instructors {
display:grid !important;
grid-gap:10px;
}
.single-course .course_element_text .course_instructors {
display:grid !important;
grid-gap:10px !important;
}
The third one seems to be some cache issue as the image is correct in the single course page so try clearing your site cache and check if the problem is resolved.