It depends on various factors. Sometimes the adaptations stay very close to the manga, but other times they might make some changes to fit the medium or add their own twists.
To read relationship manga effectively, first, familiarize yourself with the art style and the way the author conveys emotions. Then, try to immerse yourself in the story and relate to the characters' experiences. Also, take note of the dialogues as they often reveal crucial aspects of the relationships.
You might find some free relationship manga on certain legal manga platforms during their promotional periods. But be careful as many free sources might be illegal and of poor quality.
You can start by looking at the cover and the blurb to get a general idea. Then, read it carefully and pay attention to the characters and the plot development.
Well, to understand Manga Volume 2, you need to have a good grasp of the characters and the plot from the previous volumes. Also, pay attention to the art style and the details in the panels.
I'm not sure exactly. It could be that 'We' refers to a group of characters in a particular manga or maybe it's about the creators of manga. Hard to say without more context.