Actually filling a crack that wide is not too tough if a proper backer rod is used. Backer rod comes in various diameters, and is used to reduce the quantity of caulk that is used. Your goal is to keep water from getting down in there and causing more damage due to freeze thaw type effects.
right on the thaw and freeze effect but Ive seen cracks filled and they look really ugly so IF I can get that filled any suggestions on a skim coat or something to cover the crack filling I was told by a concrete man that the crack couldn't be filled nothing to do but tear up and start over I want to entertain on that patio so would like it to look nice
If the slabs are stable you can always do a tile over lay, or overlay with some other pavers like in this post where granite was used