You can't jump into football like you can jump into combat sports or B-level American sports like handegg, even if you're an "A-level athlete".
If you want to be a professional football player you need to start training even before your teenage years and play routinely since then. The technical level of even say 2nd Brazilian division would be too much for anyone who hasn't played his entire life.
Messi started training for some local club at the age of 4 and at 12 years of age he already moved to Barcelona in Spain. Cristiano Ronaldo also started training as a child and moved to a reputed Sporting Lisbon youth team at 12 and was semi-pro at 14 already, focusing only on football since then. Look up the info for any decent player and it's a similar story.
If you haven't started playing football as a kid you have absolutely no chance. Aldo started young but he also missed the crucial years of your development as a football player which is from 18-25.