Mom is 90 yrs old, mom just lost her eyesight from macular degeneration, on oxygen 24/7, live with her we need a plan B large phone.

This is a federal program https://www.icanconnect.org/#:~:text=Equipment%20and%20technology%20iCanConnect%20provides%20free%20equipment,assessment%20to%20determine%20the%20best%20equipment%20solutions.

If she has Alexa or other "smart" device she can ask the device to make a call. This would be a verbal command so no need to dial a phone.
There are other devices for visually impaired. Any "smartphone" will do voice commands. specialized devices like Jitterbug designed more for "seniors" have simple voice control for functions.

Contact services for the blind in your area. They may offer training, support, devices and other help.

I suggest you contact your County Office of Aging and Office of Disabilities. They can help find resourses and maybe free equipment.