How to start in IT without a degree as a freelancer?

My husband needs to think about a career change. He's been self-employed most of his life, doing physical jobs. He is now almost 40 but due to an illness his bones are getting weaker and at one point he needs to think about desk job. He is not really employable as he has no office experience whatsoever but he has worked from home in the past for a telemarketing company.
He is quite IT savvy but more on a hobby level. We were looking into things he could start learning now (he is still in his job) - he is into Linux and loves fixing other peoples computers (data recovery etc)..He was looking into SEO and although the internet has quite a few positive things to say about going into SEO as a freelancer I spoke to a few people from that background who said that most companies would go for agencies and couple it with website developement etc.. It's hard to get into the market now especially in Britain and you need to be really experienced - it's not as easy as it sounds. Also, my hubby says he hasn't got enough confidence. Is there anything he could start looking into which might be needed in the future? (a friend of mine is a freelance SEO only and he is doing well but he started when SEO was first introduced)...Anything that doesn't require a degree? All his other talents are more for physical jobs so we really need to find a solution for the long term.