Welcome, Tony, I'm new myself. I also hadn't been on a bike for 20-25 years. I ride a hybrid, so I can't recommend a bike for you.
As far as stamina goes, I started with 5 miles a day, 5 days a week, for a month. Then I bumped it up to 11 miles a day for a month. Then 16, then 20, and I am currently doing 25 miles per day.
Take it slow and enjoy!
BTW, where are you from? I recently moved from San Diego.