I am a 92 years old Chinese American living independently in Thailand wish to live in China. Help.

Well, do you have relatives in China?
If yes, you need to apply for Q1 Visa. In this way, you can stay in China for one year in general.
Otherwise, you can just apply for China Visa. This visa can allows you to stay in there for a few months.
Maybe you cannot apply for Foreigners Permanent Residence Card. This card needs applicants who have already lived in China for 5 years.