This might be a good start:
https://youcanfly.aopa.org/
And something you can do on your own is making sure you don't have any show stoppers from a medical certification standpoint.
Read this example of
FAA Form 8500-8, especially the instructions and questions for questions 17, 18, and 19.
Question 17 ask for medications that have been prescribed. While many are allowed by the FAA and are no big deal, others are worm can openers that will lead to the FAA reviewers wanting to dig for more info. (For example, if you take Lisinopril, and don't disclose you're being seen for elevated or high blood pressure, then the reviewers are going to hold up your application until you have satisfied them on the reason you are taking that drug)
Question 18a through 18x. A key phrase is "Have you ever in your life..." had one of these medical conditions. If you did, disclose it. And you must not lie by omission as doing so will cause monster butt hurt in the future. If you are currently being treated for the condition, additional details from the treating physician will be needed. Do be aware that some medical history items, especially 18l through 18q, may keep you from obtaining a medical unless specific (and possibly expensive) additional steps are taken. 18u, Hospital Visits, may require obtaining copies of notes/charts from the hospital.
Question 18v tackles the question of if you ever had a law enforcement encounter while under the influence of alcohol or any other substance. This can include DWI or DUI or Public Intoxication. When this applies to an applicant, many additional steps will be required.
Question 19 applies to doctor visits. Like medications, often this is easy simple and no big deal. But if you stated you went to see someone like a cardiologist or other specialist, be prepared to provide a detailed explanation about what the visit was for and what the outcome was.
At the beginning, this can sound a bit daunting, but my point of including this is to ensure you know what to expect as you work toward your dream of flying an airplane.
A key item is,
do not go for an FAA medical examination until you know with a certainty beyond 100% that you will pass. Going for an "live" examination and becoming denied will remove the possibility of flying under the Sport Pilot rules and many other powered flight opportunities. So if you have any questions about your ability to pass the exam, seek out an AME who will perform a consult. If you have some really thorny issues, seek out a Senior Difficult Case AME such as Dr. Bruce Chien,
www.aeromedicaldoc.com