I live near ambler, pa. Are there any hospital that an adult could get a free blood test?

Not sure . . . There are hundreds, even thousands of different blood tests, so it depends on what you are looking for. Decide what test you are looking for, and then see if there is a community screening program for that disease (hepatitis b screenings are done free in certain communities, by non-profit groups). Contact your local community clinic (usually don't need insurance) for more information.