I'm a noob to owning a budgie so take my advice with a grain of salt.
That said, our budgie was on a poor seed & dried fruit diet when we got him. I started mixing pellets with human-grade millet in the morning (because millet is his absolute favorite). I experimented with a few pellet brands and found that the Harrison's high potency superfine was something he'd gobble like the millet while he was pretty indifferent to Roudybush and Top's. He's now eating that in the morning, I give a human grade seed mix I make myself in the afternoon, pour it in with the pellets and he eats some of everything. I'm also working on getting him on fresh foods, he'll eat some things (they have to be small, like sprouts or cut up fine) and he also will nibble dried bird greens.
That said, our budgie was on a poor seed & dried fruit diet when we got him. I started mixing pellets with human-grade millet in the morning (because millet is his absolute favorite). I experimented with a few pellet brands and found that the Harrison's high potency superfine was something he'd gobble like the millet while he was pretty indifferent to Roudybush and Top's. He's now eating that in the morning, I give a human grade seed mix I make myself in the afternoon, pour it in with the pellets and he eats some of everything. I'm also working on getting him on fresh foods, he'll eat some things (they have to be small, like sprouts or cut up fine) and he also will nibble dried bird greens.