HI:
Goodluck.
It may turn out that you don't want to be an airline pilot or pilot of any kind. IT TAKES A GREAT DEAL OF MONEY to do what you want to do.
DO you have the money? I mean enough to buy a small house.
The school doesn't really matter as you might do better by being a good pilot.
It is not like any other profession you can imagine. You do not progress in school to the job of your dreams. Its not like you go to Stanford and get a degree in engineering and have Boeing or NASA recruit you.
Have you taken a flying lesson at all? Go out and take a "DEMO" lesson and try different types of planes to see if you are more comfortable with one type over another. Same with instructors.
If you told us where you live, we might steer you towards a flying school.
And Airline Transport Certificate is the official term for the pilot's license.
All pilot's licenses are technically called, Airman Certificates.
1500 flying hours are required for an ATP (airline transport pilot cert). AND unless you are lucky enough to get a job with a commercial cert at about 250 hours, you may have to pay for all of those hours.
Take out your calculator and multiply 1500 times 150...let me know what that costs you.
And that's the cheap way.
Many people gain hours by teaching others to fly...but it is hard work and does not pay that well or reliably.
So...think
BUT take a lesson and talk to the instructor!
And if you do have any health issues, better to find them out now. The flying school will tell you which doctors to see to get a Medical Certificate.