For "country" as a nation or land:
* país (pronounced "pah-EES") is the most common and general term.
For "country" as a style of music:
* música country (pronounced "moo-see-kah COUN-tree") is the most common way to say "country music" in Spanish.
For "country" as a rural area:
* campo (pronounced "CAM-po") is a common word for "countryside" or "rural area".
* el campo (pronounced "el CAM-po") is the definite article used to refer to "the countryside" or "the rural area".
Let me know if you have any other questions!