This is a pattern for Oscar the Grouch, from Sesame Street. Smallish, about 4 inches tall at the end, but size will vary by tension or the size of hook you choose to use. Would say it is easy difficulty and but not beginner friendly necessary. You may want to have an understanding of reading amigurumi patterns before trying this one, just in case.

Outside of standard crochet materials, you may want some needle felting supplies for the facial features. But you can just use regular felt in white, black and brown and glue on the details instead.

Green
grey
white
Black
brown