Great advice, and great support !
But, there's always THAT PERSON who has THAT BIRD. I'll tell my tale...
The Rb was an angel until he becam a rooster at about age 4. And then, he became a raging, demanding little stinker. He's a fun mimic and an entertaining character, but..
I have reduced biting to almost zero over the decades... not because I've changed the bird, but I have changed me. And a lot of that has involved giving up on a lot of my desires/expectations. After years of battle, I surrendered. I don't do stuff that gets me bitten. I don't scratch his head much, ever... tail is okay. I NEVER do stuff that makes him mad... I don't touch others when he's out; I rarely try to get him to step up onto my hand first. Hand-held perch first, then hand. In some ways, I swallow my disappointment at having such a little monster for a pet, but he is what he is. I ALWAYS wear my hair down when he's on my shoulder, so all he can bite is hair. Really, I don't involve hands much... he doesn't like them. He seems to think the real ME is my head, perched on a weird moveable tree with questionable appendages.
Since he's fully flighted, the ONLY way I get him into the cage is to toss a chile pepper in and he flaps in after it. So food reward is a necessity for me. Time-out doesn't exist in the Rb's kingdom.
But please... listen to and try all the good advice you'll get here. Don't surrender until you know you've done your best. Then just accept and love whatever/whoever your bird turns out to be.
My darling is kind of a worse-case scenario, but we have it all worked out between the two of us.
Very, very best of luck to you.
Good for you for reaching out!