You have to be a US citizen to enlist with the Marines. Meet the physical/mental/and moral standards. Studying is required to pass the ASVAB. Have a High School diaploma and be between the ages of 17-29.
You must have a high school diploma, or a GED and sufficient college hours. You must score at least a 50 on the ASVAB and have no more than four minor non-traffic infractions (otherwise, you must get a waiver). You must be physically fit and in excellent health with an appropriate height:weight ratio.
There are both legal and physical requirements. The first qualification is that you cannot have any felonies on your record, and you should be a US citizen in good standing. You must also be a in good physical health and at least 18 years of age.