One Vine is processed into 4 Twines each.
Twine is then used as a raw material for crafting recipes, mainly for armor.
Twines are crafting materials that cannot be put in any quick bars, cannot be consumed and cannot be placed into the 3D Creativerse Worlds, different from blocks.
Vines can be found on Cragwood-trees in Forests and Woodlands occasionally, also in the Jungle all over the big Wildwood-trees in large amounts. Vines will also hang down from Wildwood-trees here and there in long strands that can be taken without needing Power Cells for this.
Vines can also be obtained from some kinds of Leafies either when killing them and taking their Loot Bags or after taming and feeding them (optimally their favorite food), after which you can harvest from your Pets.
When growing Cragwood-trees from Saplings in a fitting biome like Forests (mind that Grassland often does not support trees), sometimes specimen with Vines will grow from the Saplings, especially if you have planted 2x2 Saplings together.
You can climb on Vines much like on ladders, and you can also place Vines freely.