Disclaimer John do not watch or read this post :lol:
Pepboys Auto Zone or even Walmart have small cans of R134a(providing your car is 1995 or newer or has been recharged since 1995) I recommend the cans with the gauge on them
View attachment 7520
Hook the line off the can to the low side A/C line(the only one the adapter will fit on) usually has a blue plastic cap but may be black depending on manufacturer and year
View attachment 7521 charge until the gauge is in the green.