Do you go to college, then B.L.E.T( Basic Law Enforcement Training)

In general, you're not required to complete your college degree prior to attending a law enforcement training academy. However, it becomes more difficult to complete while working full time or other changes in your life. I completed my bachelors degree after being hired, working full time. Later, i completed my masters degree while married, one child and a pregnant wife and working full time. It can be done, but it becomes more difficult.
While completing your college degree (before hand) you can possibly do an internship with a law enforcement or related criminal justice agency. I did an internship with a Juvenile Justice Advisory Committee while in college.

As a side note - i'd recommend a degree in public administration, it would broaden your career options later in life. Nothing wrong with criminal justice degrees but it won't generally make you a better officer. Explore psychology, sociology and electives that while give you a better understanding of the community you will be serving. Best of luck.

Most law enforcement agencies will send you through their own basic training.