While wearing this amulet, you can use an action to name a location that you are familiar with on another plane of existence. Then make a DC 15 Intelligence check. On a successful check, you cast the plane shift spell. On a failure, you and each creature and object within 15 feet of you travel to a random destination. Roll a d100. On a 1–60, you travel to a random location on the plane you named. On a 61–100, you travel to a randomly determined plane of existence.

This specific part right here: While wearing this amulet, you can use an action to name a location that you are familiar with on another plane of existence.

Does this mean you need to verbally speak the name/location? Like, could I just think of the location and have that work as well? RAW/RAI answers only please (preferably RAW)

Well, simply naming the location could be interpreted as determining the location in your mind, but successfully casting the spell involves a verbal component.

The RAW answer depends entirely on how the GM chooses to interpret "name." If you ask me, just thinking of something is not naming it.

I would say you have to name aloud. Most magic items require a command word, I'd treat it as that.

Quote from MilestoGo_24 >>

Well, simply naming the location could be interpreted as determining the location in your mind, but successfully casting the spell involves a verbal component.

A magic item only requires components for casting if the item's description says so.