Not going to last, as mentioned by other commenters, but if you just want a fix for a year or two:

Rent a pressure washer, clean off the surface, all the cracks.

Make sure the surface is damp. Mix up a bag of ready to mix concrete, pour it on, level/spread it (screeding) with a 2x4. A large drywall trowel or something similar can be used to get a nicer finish.

About a $15 'fix'. And as the others say, in a couple years it will probably break apart.