This The Last of Us 2 Walkthrough for Chapter 6: Seattle Day 1 – The Forward has you back at the base and has locations for all collectibles which include 1 Artifact, 3 Coins, and 1 Workbench.
The Forward Base Walkthrough
Interact with folks with speech icons for more dialogue/story.
Coin – California
As soon as you exit the truck, look to your right to see a group of four WLF Soldiers chatting. There’s a small ramp right behind them with a red railing, and you can find a coin by going up behind them to find it near the railing.
Move ahead and go through the door to check-in at the base.
Coin – New Mexico
As soon as you enter the base staging area and get checked in, you can spot a large group of WLF Soldiers chatting on your left, in front of a tent. Make your way around the group to some green crates to find a coin left on top of one – by a soldier sitting on another green crate.
Workbench Location – Tent Full of Soldiers and Supplies
Continue deeper into base, a peer will approach you. Follow them. You can get some extra supplies in the tent of soldiers. There’s a bench there too.
Artifact – WLF Interrogation Note
After your fellow soldiers show you what they’ve been hiding you’ll walk into another building. As soon as you enter, look to the table on your right, under the large framed picture, for a note.
Coin – South Carolina
Move to the dinner table, opposite of the note and pick up the coin to add it to your collection.
Continue ahead, through the interrogation areas, and then talk to the man in front of the elevator to talk to Isaac. A cutscene will play and lead into the next section Seattle Day 1 – The Aquarium.