Your arms should be comfortably bent at the elbow when you are holding the handlebar grips. Your back should be relaxed and comfortable. There are many other things you will need to know about bicycling in today's world. Bicycles have become so individualized that you will benefit by visiting a bicycle store and acquainting yourself with gears, dropped handlebars, all-terrain or mountain bikes, and special seats for the squeamish. If you see that biking on the streets and paths is for you, remember that the rules for endurance exercise are the same.
Stationary bicycles are more user-friendly and come either upright or horizontal.
They're not so expensive that home use is impossible. You can read, watch the news or soaps on TV, or rent a movie. They are an attractive alternative to a health club. Remember to measure for the proper height of the seat so that your legs are straight when you are at the bottom of the pedaling cycle. Also remember that you must warm up before and cool down at the end.