Can a lame legged man(left leg lame) become a pilot in the airlines if everything else is okay?
That depends upon how you deal with that disability. You can get a Statement Of Demonstrated Ability document from the office of the Federal Air Surgeon. After that everything else is routine.
I have known several private pilots with no legs who received a SODA to fly privately. I know there are unusual cases where a military pilot received a SODA to fly big airliners with one leg missing.
I think you could earn one if you were really determined and if whatever condition that caused it isn't likely to recur or change over your life.
In general, however, airline pilot jobs are very scarce, so you would be facing a significant battle. There are plenty of other flying jobs if you really love aviation --but don't expect them to pay all that well.
Aviation suffers from a ridiculous degree of governmental regulation. Many talented people pour their hearts and minds in to this field, and they have very little to show for it.
I won't dissuade you from pursuing a career as an airline pilot, but I have to warn you that the competition is fierce, arbitrary, and unrelenting.
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