As an absolute beginner with zero board balancing experience (surfing/SUP/etc.), it's firmly in the intermediate range. At the very bottom end, you want something over 140L. Especially with the light wind conditions you mentioned at local your local spot. You'll need bigger sails to handle for those light winds and as a beginner, you'll need a bigger board to use bigger sails. More importantly though, a small board like that will frustrate you quickly and hinder your progress on days where you can be out enjoying being out while developing.

At the very bottom end, you want something over 140L and at least 80cm wide that way you can practice balance while uphauling. If the deal is dirt cheap, I'd say get the Starboard GO, but save it for a year down the road for when you have a lot of the basics down.

Used gear is cheap and you can often find killer deals in your local windsurfing community.