To play with friends in Elden Ring, you will need the Tarnished Finger and the Furlcalling Finger Remedy. The Tarnished Finger is required to drop a summon sign so that you can join either a friend's game or other games.
You will also need to be in a boss area with an undefeated boss to use either the Tarnished Finger or Furlcalling Finger Remedy.
That being said, you can get a Tarnished Finger by looting one off a body at the start of the game. After you get a Tarnished Finger, use one near a boss area and wait to be summoned by either a random or your friend.
If you want a friend to join your game, you will need Furlcalling Finger Remedy. You can get the Furlcalling Finger Remedy by looting it or by purchasing it from the Merchant found at the church.
You can find the church in the location shown below, and the Merchant will sell the Furlcalling Finger Remedy for 100 Runes in the game. Buy the Furlcalling Finger Remedy, and you will be able to craft it, but only if you have a Crafting Kit.
Luckily you can also purchase a kit from the Merchant for 300 Runes. You can get runes from killing enemies, so we recommend farming if you don't have enough.
Once you have both the kit and Furlcalling Finger Remedy recipe, you will be able to craft one with two Erdleaf Flowers. You can find Erdleaf Flowers throughout the starting area near bushes and grass. After getting the required flowers, head into Item crafting under the inventory menu.
After crafting one Furlcalling Finger Remedy, go under multiplayer. Under multiplayer, click the Tarnished Finger and set up a password. Your friend can then use this password to join your game when accessing your summoning sign.
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