Both Fiji and Tahiti are similar to each other but and they're somewhat close to each other but not real close.
The distance from Fiji to Tahiti quite a bit and around 2,136 miles so I would say that Fiji and Tahiti are pretty far from each other.
It would take 4 hours and 47 minutes of flight time to get from Fiji to Tahiti so the islands are similar and a bit close but they are far apart from each other.