We adopted 3 older flighted budgies into our flock and they were poor flyers to begin as they were cage bound their entire 2~3 years they were owned. However, after as little as a week they learned the house and what was a wall and window and avoided slamming into it. We gave them a month+ of "cage only" time so they were familiar with us and our household in general before even letting them out.
Once they were let out we did it in a controlled area, our bedroom, and allowed them to become familiar with this room every time they were allowed to fly. Now they know where they can and can't land/perch and avoid walls like pros. It takes time in a new home.
Our babies are also starting to become flighted again, and doing the same wall slam as they're still new to flying and missing some feathers making turns/hovering harder on them. We bought them as clipped birds but I'm letting them all grow back out. Giovanni, our oldest baby, "escaped" one day and flew around the livingroom slamming into walls endlessly in a scared fit, but after giving him some fly time in our room since he seemed ready to give it a try, he also learned quickly like the flighted adults where the safe spots were and that walls were bad. He has about 2/3s of his primaries back in now and is a pretty good flyer.
I'm not saying "don't clip", it's a personal choice. We were forced to clipped our sun conure adoptee because she thought she ruled the roost and was misbehaving, the previous owner had always clipped her so her new found flight made her very bossy and hard to handle.
We only had a 'half clip' done allowing her to glide (outside primaries are still intact) and letting her grow back out to see if she's learned her place. Already she has a lot of flights coming back in from this fall molt so I guess we'll see how well she learned mommy doesn't like bossy birds.
The "half clip" was recommended by our avian vet who did the trim saying for larger birds that they can still have some feathers left making it less traumatic and easier to grow back out, but she mentioned in the case of budgies they're so small they can fly even with half their flights missing, as our second oldest, Bones, has shown us. He only has one wing grown back in and he can fly reasonably well, just kinda crooked, poor fella.
Whimsy
Owl
Waker
Berkie
