no
You get it from a girl in Cianwood after you beat chuck.
cianwood city
If rocks are blocking off Cianwood, then you're playing Beta 2, which is a REALLY old version of the game. Don't feel bad, my cartridge had Beta 2 as well.
go to olivine and surf south-west
its the lower house with the sign in Cianwood city
Fly in CianwoodThe HM Fly is given to you by the lady (who is the gym leader's wife) outside Cianwood Gym, but only after you've beaten the gym leader. She will comment on how her husband is getting fat! ;)
you catch a mantine on route 41 next to cianwood cityWhich version are you talking about? Cianwood City was in the Silver/Gold/Crystal versions. In Leaf Green, Mantines are found in Tanoby Ruins and surfing near the Trainer Tower.
Chuck is found on Cianwood City Use surf until you pass route40 and 41... be careful of the whirlpools
surf to cianwood city. check the pharmacy for the secret potion. go back to jasmine. done
After you beat Chuck, leader of the Cianwood City gym, talk to his wife who is walking in front of the gym. She'll give it to you.
If you have brought the medicine with you from Cianwood, you just have to talk to Jasmine. If not, you'll have to surf to Cianwood and talk to the man in the pharmacy. Make sure you've spoken to Jasmine first, or he won't give you the medicine. Also, pick up Strength first, so you can beat the gym in Cianwood and fly back to Olivine. If not, you'll have to Surf back... Then talk to Jasmine, who will return to the gym.
Get HM Surf from the man in Ecurteak City. Use it on a water pokemon. If you don't have one, trade from a different version. Go through the water and you will find Cianwood city.