The best way is to focus on one quest at a time. Read all the quest dialogues carefully as they are full of story details. Also, make sure to complete any side quests that are related to the main story arc as they often provide additional context.
After returning to FFXIV, the story quest could be initiated by visiting your class/job trainer in the corresponding city or by checking the notice boards in major hubs. Sometimes, you might receive a message or prompt directing you to the right place.
The story of FFXIV 1.0 was a mixed bag. Some aspects were engaging, but it had its fair share of flaws, like inconsistent character development and a confusing overarching narrative.
The Heavensward expansion has an amazing story. It focuses on the Dragonsong War and the relationship between man and dragon. Estinien's story arc within this expansion is really engaging. He starts as a dragon - slayer with a one - track mind but as the story progresses, he grows and changes, learning about the deeper issues between the two races. And the landscapes in Heavensward add to the overall atmosphere of the story.
The length of the FFXIV story can vary depending on how quickly you progress and how much side content you explore. Generally, it's a substantial and immersive narrative that can take a considerable amount of time to fully experience.