Filling crack in outside concrete path
There are several types of concrete patch’s available at most home stores I like latex type products because they are flexible . All you will need is a calking gun and a tube of the proper type, give a big box store a try tell them what you want show them the photo.

When they make a recommendation if they don’t provide a reason (like I said I like latex because it remains flexible and will not break up with summer heat and winter cold) ask them why they like that brand or type. 

This is as close as I can get without it turning into a shopping question that would be off topic and closed.