Stick with the route you're going down - join the RAF (I assume in an engineering trade).
Good training, good experiences, excellent grounding for becoming a civvie aircraft engineer in the future, you'll make friends that will be with you for the rest of your life to name but a few of the reasons to do it.
On the downside there will be detachments away from home on a regular basis that can / will affect home life.
At 22 years, getting an apprenticeship will be very, very difficult - no funding from government to the employer for a Modern Apprenticeship.
Going down the college / ab initio training route gives you the theoretical knowledge (at your own expense and it is not cheap) but almost zero practical, hands-on experience that employers want and need. There are many, many people who have gone down this road only to find nobody will employ them and they give up on the industry with a few years of their lives wasted and their bank account rooked.
Join the RAF, stick in, learn, have fun and do your licences before leaving in a few years time.