Thank you for your reply,
1. I just did that, the HEADER (logo and menu on the home page) did change to the mobile size, but the rest (POST/PAGE/FOOTER/ when Menu expanded)the size of the font still remains the same. What should I do?
my URL https://wabisabi.one
2. I am not too sure about the Excerpt, I manage to google the location which is on the Post Edit screen and Page Edit screen (correct me if I am wrong). I open my About page and empty the Excerpt, Save, and the caption still appears below the Title. Any solution?
3. Manage to get 90% of the layout, but I realize there is a comment box, how do I remove that?