Tested some custom resources with a test scene.

scripts/bullet_stats.gd

@@ -0,0 +1,15 @@
+class_name BulletStats
+extends Resource
+
+@export var bullet_type: String
+@export var bullet: String
+
+@export var damage: int
+@export var speed: int 
+
+
+func _init(bullet_type:String = "normal", bullet:String = "res://resources/bullet_resource.tres", damage:int = 1, speed:int = 150):
+  self.bullet_type = bullet_type
+  self.bullet = bullet
+  self.damage = damage
+  self.speed = speed