Congratulations on your new acquisition. You may consider changing the title to "My first Motorized ride" unless you had a diesel powered ride before.
you got me nostalgic, back to the days when I was your age.... had a couple of french motobecane mopeds.... sweet ride but a bit difficult to maintain due to non-availability of parts.
As for fuel consumption, the first thing to check is of course the carburator settings followed by ignition timing, valve clearance etc (if 4 stroke)
Scooties typically have a centrifugal clutch. If the clutch pads have worn out, your engine will have to apply extra force to engage primary drive with the engine; resulting in excessive fuel consumption.
If your scooty is 2 stroke, you may want to check the "suction plates" and their allignment. Caveat!!! DO NOT ATTEMPT TO ALLIGN SUCTION PLATES YOURSELF IF YOU ARE A NOVICE. Trust a capable mechanic (ideally a rickshaw mechanic) to do this job....
One small suggestion. All your scooty needs, besides periodic maintenance, is regular wash and wax. Keep it stock, no silly mods in the name of "desi" aesthetics.