Some skills take longer to learn than others. You can learn to dig ditches with a shovel fairly quickly, but it takes more time to learn to operate a Ditch Witch. One person can learn to lay bricks efficiently in less time than it takes a more clumsy person, but it still takes time. Pouring concrete does not take a lot of skill, but finishing it takes practice.

Get a job with a construction company and learn on the job. Or decide on a trade you may like and look for a job with a specialist in that trade: Plumbing, rough carpentry, finish carpentry, wiring, painting, roofing, etc. As you acquire skill in your trade, you can then start on your own.

You could also become a Jack of All Trades, or Handyman. They seem to be always in demand.