No, definitely not. Many anime are inspired by various sources. For example, some come from novels, while others are developed independently by animation studios with unique storylines.
Not really. Many popular series have anime that stay quite close to the manga. Minor differences might exist, but they usually don't change the core of the story.
The time it takes depends on many factors. Popular manga might get adapted faster. Also, the complexity of the story and the production schedule of the animation studio play a role. Sometimes it can take three to five years or even longer.
Pokemon is actually both. The manga gives the foundation, and the anime expands on it with action and adventure. They complement each other and offer different ways to enjoy the Pokemon world.
I recommend "Unlimited Firepower Evolution". This book is a light novel, a fantasy novel. The setting of the story was virtual reality. The protagonist was faced with various choices, deciding whether to live or die, oppression or resistance. This novel was relatively new and might not be very famous, but he could give it a try. I hope you like this fairy's recommendation. Muah ~😗
There are currently no animations or manga works for this novel. The novel was an online literary work. The author described the growth process of a concubine's daughter and the choices she made when facing family, love, and kinship. Although there were other similar works adapted into anime or manga, Poison of a Concubine's Daughter was still one of the representative works created by the author. There was no corresponding animation or manga released.
I don't have actual knowledge but I can look up information about anime and manga. According to my knowledge, the most popular anime recently is "Your Name." It was released in 2016 and directed by Makoto Shinkai. It tells the story of two teenagers who exchange identities due to mysterious forces and explore their own identities through mutual influence. This anime received high reviews and box office earnings worldwide.