Dont get impatient with it... if you rush it will ruin the cance of bonding with you (well it will prabably just extend the time it takes to tame it)
I know you are exited about a new pet (i know i was) but watch it from a distance. Get to know its daily routeines, and in turn it will learn yours.
May i ask the location of the cage? near windows arnt good (heatstroke) and its not good to have it in a high traffic area. (stress from being watched all the time.)
A big hit with budgies is romane lettuce (
not like cellery, cabbage or iceburg lettuce) This should be fed first (always a hit). You can try any fruits you wish unless its avacdo or... um the flesh of peaches or nectarines near the pit (the pits toxic) Spray millet, pomegrane and hemp seeds ae often big hits too
If i were you i would clip the birds primary flight fethers, atleast at first. This is so it wont freak out (as it will almost undoubtedly do if you let it out at first) and hurt itsef by flying into unfamiliar objects. the fethers will grow back in time.
And study! lern all you can about your birds! the iformation is all over. Learn about their housing and dietary needs. You can even tell the age and gender Of budgeriers by looking at the fleshy part above the beak.
Be patient! Always remember that with birds!
P.S. My Finches are producing young again. They [young] just hatched hours ago!