Stratford Career Institute is not regionally or nationally accredited. This probably does mean that its acceptance will be minimal.
You have a couple choices:
1. Earn the GED. If you have the knowledge to pass it, there are colleges that will accept that in lieu of a high school diploma. There are GED preparation programs both online and off-line. I would encourage you to check with your college of choice first, though.
2. Earn an
online high school diploma. You might even find one that is willing to accept some of your work from Stratford (but no guarantees; I really do not know).
As to adult high school diploma vs. high school diploma: they can be the same thing or they can be different based on which state you live in. Either way, you only want a program that is accredited.
If you are not sure of the accredition, feel free to come back here and post. I am happy to help you in making the right decision.
Tom Nixon