This is a general course to give you a familiarity with coding that you may encounter as a marketer.  At this point, you are not expected to know how to code websites or use CSS to make changes in the code.  That being said, you are also not to make changes, unless you: 

1. have authorization to make changes, AND

2. are already proficient in HTML & CSS, OR

3. have taken the main web design course on Udemy.