I started out with my dad on HGV vehicles so it is possible. I got into aviation through a chance meeting with my previous boss. If you can get an apprenticeship I would recommend it, failing that find out the local airport to you I'm sure there will be a small airport somewhere near find the maintenance organisation and go introduce yourself it goes a lot further than sending in a cv you will start at the bottom but if your willing to learn then you'll be fine. This is my personal experience working in small general aviation I can't speak for wide body or helicopter but I hope it helps .