I have a cement platform that leads to cement steps which in turn lead
to another cement platform before entry to my house. The first cement
platform has one inch cracks that ride up against the foundation wall
on one side. The platform after the steps that lead to the house
entrance have a few patches of missing concrete that need to be filled
in on the outer side of the platform away from the house.

My question is, should I use Mortar Mix directly to repair the cracks
and missing concrete or do I need some bonding agent before I apply the
Mortar Mix? Should I use Mortar Mix for this repair or something else?