Depending on system.
Where I am, with all basic fire for the majority of calls, if they arrive first, they get a good basic assessment and a set of vitals. For critical patients, they do cpr and help with the manouvering and movement of the patient.
Video taped practicals? Is this a new requirement? When I took the course last year we just had a proctor who signed us off after performing the skill.
It is possible, but difficult. If there are absolutly no places near you that hire under 21, look into volunteer services, if there are none, look for ER tech.