As one of the Groot Awakening Challenges, you'll need to plant a seed on a heart-shaped island in Fortnite. It's a fun little challenge that ties in well with the fact that Groot is basically a tree.
The first thing you need to do is equip the Groot skin which you can unlock at level 38 of the Battle Pass. You'll need to reach level 46 before you can complete this challenge, so you'll definitely get the skin. After that, head to the heart-shaped island, which you can find on the map below.
Make your way to the island, though the easiest way to get there is to just walk there directly from the Battle Bus, and you can easily see a patch of brown dirt on it. Go ahead and interact with it to plant the seed.
Once that's done, you're halfway to earning the special Rocket Racoon emote that Groot can get. The emote is, frankly, amazing, as Rocket Racoon will fly around Groot, looking for enemies and threats. It doesn't actually do anything, but it's a very nice touch for the skin.