How can I help?
Guardianship....learn more about it and the process on the internet. Information is free.
they think he had a stroke and his blood pressure is very high and I know for a fact he has a touch of dementia (early stages)
Likely it's all inter-related. Dementia can result from stroke. Some of the same underlying causes for certain types of dementia can also precipitate stroke.
Tell us what you know of his financial and medical situation. Insurance beyond Medicare, assets, liabilities, etc. If he's in an independent living facility or AL, he's got assets. They'll be important for his future care, if he cannot return to his current arrangment.
Just do your best and remember him for the great guy he is/was. Let us know if we can help further.
Pat