Dragonite, ho-oh, lugia are not in the game, you can't get them.
There are 400 pheromone in the galar dex that are available:
https://www.serebii.net/swordshield/galarpokedex.shtml
There are 35 extra Pokemon which can be acquired with PKHeX or cheats: Bulbasaur, Squirtle, Rowlet, Litten, Poppilo families. Mewtwo, Mew, Celebi, Jirachi, Cobalion, Terrakion, Virizion, Reshiram, Zekrom, Kyurem, Keldeo, Cosmog, Cosmoem, Solgaleo, Lunala, Necrozma, Marshadow, Zeraora, Meltan, Melmetal.
If the Pokemon you want is not in that 435, it is not in the game. you can't spawn it, you can't use it. Don't bother asking about it because there is no way for anyone to make a code, or a save that will get you them. Best you can hope for is a rom hack, which is months if not years away where the pokemon are added in but right right now