Are You A True Star Wars Series Fan?

Bounty Hunters do not serve only the Empire. They are independent mercenaries who work for various clients, including criminal syndicates, governments, and individuals. While some bounty hunters may choose to align themselves with the Empire, others may work for different factions or operate independently. Therefore, the statement that bounty hunters serve only the Empire is false.

Jango Fett died in Episode II. This statement is true. In Star Wars Episode II: Attack of the Clones, Jango Fett, the bounty hunter and father of Boba Fett, is killed during the Battle of Geonosis. He is decapitated by Jedi Master Mace Windu after a fierce fight. This event marks the end of Jango Fett's character arc in the Star Wars franchise.

Count Dooku's Master when he was a Jedi was Yoda.

In the Star Wars universe, Dagobah is the correct answer because it is the planet where Yoda, a Jedi Master, resides in exile. Luke Skywalker is instructed by Obi-Wan Kenobi's ghost to go to Dagobah to receive further Jedi training from Yoda. This is depicted in the movie "Star Wars: Episode V - The Empire Strikes Back".

In the Star Wars Expanded Universe (now known as "Legends"), Boba Fett escaped from the Sarlacc pit after his apparent demise in "Return of the Jedi." However, in the official Star Wars canon, which includes the movies and certain TV series like "The Mandalorian," Boba Fett's story continued.
In "The Mandalorian" TV series, Boba Fett survived his encounter with the Sarlacc pit and was shown to be alive. He played a significant role in the series and was portrayed by actor Temuera Morrison. Therefore, as of my last update, Boba Fett was not killed, and his story continued in the official Star Wars canon.

Those who have blue light sabers are Obi-Wan Kenobi, Kanan Jarrus, Ezra, and Anakin Skywalker. 

During Order 66 and the Jedi Temple attack, Darth Sidious personally killed Ki-Adi-Mundi, Agen Kolar, Kit Fisto, and Mace Windu.
Saesee Tiin, Yoda, Barriss Offee, Darth Vader, Plo Koon, and Aayla Secura were not killed by Sidious directly:
Yoda survived Sidious’s attack.
Darth Vader (Anakin Skywalker) was Sidious’s apprentice.
Barriss Offee betrayed the Jedi but was not killed by Sidious.
Plo Koon and Aayla Secura were killed by clone troopers, not directly by Sidious.
Saesee Tiin was also killed by clone troopers.