How to add a collider around a multisided polygon

Yeah that’s pretty much it, which collider should I use? I included the image that I wanted to toss a collider around so that the player cannot touch it.

You likely want a PolygonCollider2D Unity - Manual: Polygon Collider 2D reference
Then edit it manually.

If you’re using a tilemap, another way would be to use a TilemapCollider plus Composite Collider.