The Mass Effect comics can be somewhat canon. They often expand on the lore and backstories of the games, but their status can vary depending on how they fit into the overall narrative framework established by the main game series.
The length of the Mass Effect story really depends on your playstyle. If you focus mainly on the main quests and skip a lot of the side stuff, you might finish it in around 20 hours. But if you take your time, do all the side missions, and explore every nook and cranny, it could easily be 50 hours or more.
The original story of Mass Effect was set in a vast universe where players control Commander Shepard and make choices that shape the fate of the galaxy.
Overall, the story of Mass Effect Andromeda is a mixed bag. It has some exciting elements and character development, but suffers from pacing issues and inconsistent writing in parts.
The story of Mass Effect 1 is quite substantial. It can take a decent amount of time to complete, depending on your playstyle and how much you explore. Generally, it could take around 20-30 hours to finish the main storyline and some side quests.