I like your moxie. As said above, get boots and a hard hat and you should be able to get paid. Working for free is scary as you won't be covered by comp if something goes wrong.
It looks like you are trying to fit this training around a full time job. Are you planning on transitioning to work in construction or do you just want to learn how to renovate your own house? If it's the latter, try to find a buddy that is doing their house and trade labour with each other.
What trades are you trying to learn? I hate to say it, but youtube is great for a lot of things. Just be sure to watch videos from many different people and pick out the common points. Some people talk like they know what they are doing but do everything wrong and/or focus on pushing unnecessary products provided by their sponsors.
Do you have access to a back yard? Building projects like sheds or decks close to the ground are great starter projects to get your feet wet. Build for friends and family, they pay for materials, you provide the labour. If things go horribly wrong, you haven't messed up someones million dollar house and the chance of injury in a collapse is much smaller.
EDIT:
Maybe even a better option is Habitat for Humanity. They are setup for this and you get to help people in need.