>>1443926Depending on the country you live in there are some requirements you'll have to meet. In some places you need to have a chainsaw certificate to be employed. I guess it doesn't hurt to bring your own chainsaw & personal safety equipment, but other than that, just about anyone can go work in logging.
You need to be pretty hardy weather-wise and shouldn't mind hard labour. The work is dangerous and exhausting.
If you don't have a problem with the above, go hit up your local forester / forest-owner / forestry services contractor and apply for a job as feller. In about two weeks you can learn most of what you need to know to handle felling regular, non-complicated trees without endangering yourself or others.