As a beginner, it's best to stick to cheaper woods like pine, whitewood, and plywood. These woods are readily available and won't break the bank if you make a mistake. Avoid using more expensive hardwoods or exotics until you have a firm grasp on what you are doing. Be sure and save scrap pieces because these can always be used for testing on before you commit to the final project piece. You may also be able to find free wood such as pallets and other scraps that others would throw away.