Best way to structure a story in Agile

Question

Story: As a business analyst I should able to see 4 new columns in the report

Estimated: 3 story points 1 story point is 20 hours == 60 hours.

So this story would take 2 weeks , 1 sprint to complete this one story for one person.

Questions are: 1] is it the right way to estimate a story? 2] can a single story have multiple people working on it? 3] Each sub-task in this story probably needs to be 6 hours per day as per guidelines in JIRA or other Agile tools. As long as the story completes in 60 hours, does it matter how many hours we assign to each sub-task? 4] In this type of estimation, this story may show pending or yet complete status for a long time in Burndown chart, is this correct?

What is the best way to structure this story for maximum benefit to customer?