This topic is very relevant considering the changes going on and health care is very important and personal. Everyone's situation is different.

I have a favorite to ask, if you mention Medicare Advantage or a Medigap (supplemental) plan, please include the insurance company and entire policy name.

As an example, BCBS has many policy and some are only available in certain states you live in. One reason is a state may have rules that insurance companies need to follow in addition to federal rules. BCBS in one state may not be available in other states or have different costs.

Example, I live in SE MN and I have original Medicare (part A & B) and a Medigap policy from BCBS MN and called "Basic Medicare Blue".
In addition I have Part D for medications from Wellcare: PDP-VALUE SCRIPT REG 25

Also, if looking for more general information about Medicare or Medicare Advantage differences, this booklet from Medicare may help:

"Medicare and You 2026"
https://www.medicare.gov/publications/10050-medicare-and-you.pdf