Do you have to take Liberal Arts?

I assume you are referring to post-secondary education, such as attending college/university.

The answer is: usually, but it depends very much upon the program and the school.

If you are going for a BA or a BS degree at most US universities, you will have some "General Education" courses you will take your first and probably your second years at the school.  This will include "liberal arts" courses, such as English, and History.  You generally will have a choice of which courses you take, provided they are on the list of courses acceptable for General Education credit.

If you are going to a trade school, or going to a community college for a trade-related course of study (such as automotive mechanics), you will have few or no liberal arts courses.  At most, you may have a course or two in applied math (which you can apply to automobiles), and maybe a writing course.

Certain first and 2nd year classes maybe. You don't have to and should not major in it/them. If a job is something you are interested in.

No. Liberal Arts include majors such as History, English, Political Science, etc.  

If you are thinking of general studies, the answer is yes.  All college students are required to take courses in such subjects as English, History, Math, etc.  General studies courses are usually prescribed by individual schools.