It depends on the crack. You do need a rough surface for grip and it is best if it is undercut, but it isn't a necessity if you follow the directions on the product. Be sure that there is NO oil or grease contamination.
The sealers are more effective than new concrete, which is why they exist. Concrete doesn't bond well to existing concrete due to the movement during the drying process. A quick dry patching concrete is actually concrete with other materials added.
The chips are a different story, due to the shallowness and the shape they can be difficult to fill. An old trick is to (carefully) drive a concrete nail into the chip and allow part of it to protrude to where it is just below the lip. This gives the material something to grip. (Predrilling and a regular nail has the same effect.)
Be aware that the cracks will most likely reappear over time unless you correct the underlying problem (many times there is no possible correction)
EDIT - I should have asked the size of the 'chips' LOL
I answered for craters at least a 1/2 inch deep and an inch in diameter. If they are really small and shallow then just fill them and hope for the best. If the sealer pops out over time then refill.
EDIT -after details added- Same thing applies in general. I won't recommend a specific type of patch because they vary in quality. Just be sure to purchase a name brand product and read the label since there may be a limit on the size or span that they are recommended for (labels for 'crack fillers'). Wish you luck. be sure to have the recommended cleaning materials on hand just in case.
As for the painting - you need to check the label for paint compatibility - you need to etch bare concrete with acid (read the can) to paint it DO IT BEFORE YOU PATCH since it may harm the patching material (to be ultra safe you may want to use a primer coat on the patch) Keep hot tires off the paint until it has fully cured - once again read that label.