Finn is one of the main characters of the sequel trilogy being close friends with Rey (another skin available in the game). The Finn skin is based on his appearance in Episode IX: The Rise of Skywalker.
You are able to purchase the Finn skin through the Fortnite item shop. If you’re looking to get several Star Wars skins, Finn is a part of the Rise of Skywalker Pack which has skins for Rey and the Sith Trooper as well for 3,500 v-bucks. Each skin also comes with a back bling. For Finn specifically, the back bling is a hologram logo of the Resistance logo.
For those only looking to get the Finn skin he is available separately for 1,500 v-bucks which also includes the Resistance back bling. While Finn doesn’t come with a harvesting tool or glider there are Star Wars related options to pick alongside the skin. We recommend the Riot Control Baton (800 v-bucks) harvesting tool and either the Y-Wing or Vanguard Squadron X-Wing glider which sells for 1,200 v-bucks each. There are also a few emotes like the Resistance Thumbs Up (200 v-bucks) and Traitor (300 v-bucks) emote.
Related: How to get the Kylo Ren skin