What am I going to need? edit
Take a moment to consider what situation you're in and what resources you have to give you a head start towards where you want to go. Then you can research what else might be available.
Important areas to contemplate:
If you live near the ocean or a substantial body of water, you've got a good start. Inland lakes offer interesting challenges and opportunities of their own. If your area offers neither of these, you my have to do a bit of travelling.
Most sailing doesn't require Olympic athleticism, but it is a sport, so being fit will be a help. There are ways to adapt sailing for those with substantial disabilities.
You'll need to learn to operate and maintain your vessel. Ability to use tools and fix things will be most handy.
Some kinds of sailing can be a rich man's game. Others can be done on a shoestring, or less. It's important to be realistic about what you can afford, lest you be tempted to commit to a course that you won't be able to afford to follow though.
Next Chapter: Sailing/Racing