Yes, the classic Konami-level trick works here. In World 1-2, there is a hidden beanstalk near the end. Climb it to reach a coin heaven. Collect all the coins, drop down, and repeat. You can farm 99 lives in about 15 minutes. You will need them for World 8.
World 6 is the filter. It is where most players quit. The ice physics in have been tweaked to be more slippery than ever. Pro tip: Do not jump while moving left/right on ice. Instead, jump straight up (neutral jump) to reset your momentum mid-air. This trick saves lives. mario forever 6.0