In British English, 'college' does not refer to University / higher education, it's closer to high-school. Garry's british and probably went to a UK college at the normal age for someone in his cohort.

The post even references this

> Our college is free and normally vocation targetted. People who leave school usually either get a job, stay on at school for 2 more years, or go to college.

To be more precise they are called "6th Form College", and take 2 years to complete. At the end you take A-Level exams* which determines which type of university you can apply for.

My mates went to Cambridge/Oxford, I didn't.

* This information may be out of date!