It depends on how well you understand and enjoy the story. If you can still grasp the plot and characters without missing important details, it might not be a problem.
You can start by creating an account on Crunchyroll. Then, navigate to the manga section and look for the titles you want to read. Some may be available for free, while others might require a subscription.
Well, it's not strictly necessary. The anime might give you a decent overview. But the manga often has more details and might offer a different perspective.
Well, if you find that you don't remember much about the plot or characters after reading, chances are you're going through it too quickly. Maybe try to slow down and savor the experience.
I'm not sure if there's a manga with that exact name. You might want to try searching on popular manga reading platforms or forums to see if you can find it.
You could search on platforms like KissManga or MangaFox. But keep in mind that the availability might vary and make sure you're using legal and trusted sources to read it.