Can you Teach Yourself or Do You Need a Teacher?
Education is a very subjective thing. Everybody learns differently and some people will learn far more quickly than others as well. The amount that you can learn individually is also a very individual thing and you may or may not be successful if you attempt to teach yourself something new without any support from a teacher.
That being said, the internet is now an amazing resource for people wanting to learn new skills, from a language to scientific theories to creative writing techniques. There are lots of websites that will support you in your venture, whatever it might be. The internet can be the teacher for many people now.
If you want to learn independently but need some support, you may be able to take a distance learning course so that you can work when it suits you, but still, have the help of a qualified teacher. This is a good in-between option, giving you freedom but also learning support.