Outdoor concrete repair/resurface/sealing and painting
Thin coatings placed on top of bad concrete, especially slabs that already have numerous significant cracks, and is outdoors will rarely, if ever, be successful. You will spend a lot of time and money to bandaid it up only to have it fail in the next series of climate changes.
Best suggestion for the mess showing in your pictures is to:

Rent a jack hammer and break up all of the existing slab into manageable sized pieces.
Clear out all the old concrete pieces and haul away.
Evaluate the old base materials. In all likelihood the base there is totally inadequate as evidenced by the major cracking in the old slab.
If necessary dig out the old base materials and follow regional recommendations to lay in proper base materials appropriate to your climate zone, soil conditions.
Prepare the site with new edge forms to define the periphery of the replacement slab.
Lay in a combination of mesh wire and a grid of tied together rebar to hold the slab together in the event that small fracture cracks occur. Make triple sure that the mesh and rebar is properly positioned so that it is within the thickness of the slab. It does no good if it is left laying on the base material with the concrete just poured on top of it.
Pour the new slab. Highly recommend that the poured mix come out of a delivered redi-mix truck so that you get a professional mix appropriate to your area / project. A home mixed or small wheelbarrow mixing done from pre-mixed bags will not yield a quality job that will last for years. The existing old concrete and how it is failing seems to indicate that it was done in the way I am recommending that you avoid.
Properly screed and finish the concrete after pouring. Professional tools should be used.
Apply proper post pour care for the concrete slab while it cures. This may include wetting it down and possible even covering if there is a lot of hot sun that can make it dry out too fast.

For the steps outlined above numbered 4 through 8 you may want to really consider hiring a professional crew to come in to do the work. Unless you have good experience with concrete this may not be a project to tackle as a DIY. If you do hire a professional crew make sure that you check out references and look at similar projects that they have completed before. Also make sure that you work with a contract that includes some responsibility on the part of the contractor to repair or replace the project if it turns into a mess like you currently have on your property within 1 or 2 years. (It is highly unlikely that you can get any type of contractor warranty for any more than a year or so).