Gandalf does not appear in
The Rings of Power Reveals When Gandalf Arrived
Their numbers included Gandalf the Grey and Radagast the Brown, as well as Saruman the White, who betrayed their mission and joined forces with Sauron during the events of The Lord of the Rings.
A c. 1960 narrative shows a conversation between Galadriel and Gandalf in the Second Age. A c. 1972 essay mentions that it's very likely Gandalf had already been visiting Middle-earth for a while and getting acquainted with its inhabitants.
Like Morgan said, Gandlaf is a Maia (spirit). That means he doesn't age like normal humans do. He existed before the creation of the world. Gandalf came to middle Earth in T.A. 1000 and left at T.A 3021, so you could say that he was 2000 years on Arda.
Over the next 17 years, Gandalf travels extensively, searching for answers on the ring. He finds some answers in Isildur's scroll, in the archives of Minas Tirith. Gandalf searches long and hard for Gollum, often assisted by Aragorn, who eventually succeeds in capturing Gollum.
Frodo came of age as Bilbo left the Shire. Frodo inherited Bag End and Bilbo's ring. Gandalf, uncertain about the origin of the ring, warned Frodo to avoid using it and to keep it secret. Frodo kept it hidden for the next seventeen years, and it gave him the same longevity it had given Bilbo.
Frodo and Bilbo were comfortable and well off until T.A. 3001. At this time, Bilbo threw an enormous party to celebrate his 111th birthday, and Frodo's 33rd, the date of Frodo's coming of age. At this party Bilbo gave his farewell speech, and made his long-planned "disappearance" and withdrawal from the Shire.
Gandalf's age is impossible to determine, but he's likely existed for at least 10,000 years, making him much older than Legolas.
Together, the two of them were known as the Blue Wizards. The one in brown was Radagast and the one in grey was Gandalf, seemingly the oldest and the least of the Order.
That said, the people behind the “official movie guide” for The Lord of the Rings list Legolas as being born in the year 87 of the Third Age of Middle-earth, which makes him some 2,931 years old around the time of the War of the Ring, which happened over 3,000 years into the Third Age of Middle-earth.
While the upcoming TV series does have the chance to bring several beloved Tolkien stories to life on-screen, none of them include Gandalf. That's because The Rings of Power will be set primarily in the Second Age of Middle-earth, and Gandalf doesn't come to the land until its Third Age.
So in Two Towers Gandalf says he has been around for 300 lives of Men.
Having Legolas appear in The Rings of Power is no more a canon distortion than having Gandalf there. The Wizards, Istari, weren't sent to Middle Earth until roughly a thousand years into the Third Age, and there is no evidence, in the books and the Lord of the Rings movies, that Legolas was born before the Third Age.
The Second Age saw the rise of Sauron after the defeat of his master, Morgoth. During this period, Sauron built his armies, established himself as the Dark Lord, and built a fortress in Mordor called Barad-dur, also referred to as the Dark Tower.
In the books, it's Radagast who sends the eagle to save Gandalf from Saruman's clutches, though the character doesn't appear in the film version. Radagast then essentially disappears from the story.
Gandalf, like all the five wizards of Middle-earth, was a Maia, an angelic spirit of the same order as Sauron.
Shelob, who is even older than Sauron, serves as a kind of guard for one of the entrances to Mordor.
In a letter, Tolkien wrote that Radagast gave up his mission as a Wizard by becoming too obsessed with animals and plants. He added that he did not believe that Radagast's failure was as great as Saruman's.
The Blue Wizards Arrived First
The first Istari sent to Middle-earth to fight against Sauron are the two blue wizards named Alatar and Pallando. Alatar had been chosen by the Valar Orome, the hunter. Alatar didn't want to go alone, though, so he asked his friend Pallando to join him.
Aragorn led the forces of the Reunited Kingdom on military campaigns against some Easterlings and Haradrim, re-establishing rule over much territory that Gondor had lost in previous centuries. He died at the age of 210, after 122 years as king.
He is far younger an elf than Galadriel and has not seen a large-scale war for himself since he was a young child. Since he had lived a generally sheltered life up to the point this story begins, Elrond is far more diplomatic and optimistic than he is in the Lord of the Rings trilogy.
Does Sam ever see Frodo again? Yes, Sam eventually gets to visit Frodo again in the Undying Lands after the destruction of the One Ring. Sam is among the Fellowship of the Ring members who set sail from the Grey Havens to the Undying Lands, along with Frodo, Bilbo, Galadriel, Elrond and Gandalf.
And he does it, explicitly, because Sam describes himself as being “torn in two” by his love for Frodo and his love for his family. Frodo knows Sam can never live a full life while he is there, suffering.