If you just save the airfoil pic (no winfoil in use) from various databases from the net, and then without changing the thickness simply enlarge with Paint or other BMP editor, will you get an accurate airfoil when printing? If not how do you enter the long list of coordinates into Winfoil or other programs, Winfoil just has 10 stations while the x y coordinates listed is a string of about 30 numbers from most airfoil data bases.

Thanks in advance I really need help.

Yes

As long as your enlargement application has the proportions locked, enlarging and reducing will "do all the math" for you.

FWIW:
It is worthwhile to pay attention to how your printer handles the output it's given, however. I had a printer a couple of years back that did not print out the dimensions it was given. If the picture was 3x5 in the pc application, the printer wouldn't give 3x5. It lost some length and a bit more width. And there was nothing in it's software that provided a way to correct it. I had to distort the dimensions in the application in the pc. That was easy, but keeping up with the saved prints in the pc was a pain. I had the good prints with correct dimensions and "duplicate" prints I'd adjusted and that was a waste and pita. So I got a better printer.

It's often a good idea to test the situation(s). I take a picture of a ruler and use that picture to check what my monitor shows and what the printer prints.