Get a geared bike, and if you want to t**t about with single speed, just don't change gears. The beauty of this approach is that you'll have 20 different ratios to choose from should the first one be inappropriate. Which it will… 95% of the time.
With a geared singlespeed bike, you can change your singlespeed while you're actually riding, so you can choose a lower gear to climb hills, or vice versa, without having to swap sprockets or chainrings in the workshop. With a bit of practice, you'll be changing ratios several times a ride!
Seriously, riding a roadbike is more about pedalling rythm. Gears allow you to pedal at a comfortable cadence which makes you quicker, more efficient and you'll enjoy it more. And before any niche-knobs say "oooh, I'm leave professional cyclists to eat my dust on my luddite machine", have you ever seen a single speed used on Le Tour? No.
So to summarise, stop being an attention seeker, grow up and buy a bike with gears.
;o)