In need of basic training plan

You'll need to "just start riding" to get a feel for what you are currently capable of doing. ~1 hr rides 2-3 times a week at a moderate effort level and 1 longer ride of ~1.5-2 hrs will start getting your legs (and butt) in shape and give you an idea where you stand.

After a couple weeks of this, try increasing your weekly mileage by about 10% per week.

Plan on drinking about a bottle of water or sports drink for every hour on the bike.