Problems when compiling with XeLaTeX

[thegreatseo]

Hello. I usually use XeLaTeX, so I tried to compile the sample tex file with XeLaTeX. It first gives errors related to the package microtype, so I deleted the parts in lecture.cls using microtype. Now I can see bunch of errors, for example Undefined control sequence. \begin{document}. May I ask you where I should modify to compile with XeLaTeX? Thanks.

I am using Windows 10, TeXLive 2020, TeXstudio. I attached the generated log file.

Sample.log