If you make a foray into a new or unfamiliar type of activity, you start to become involved in it.

You can refer to a short journey that you make as a foray if it seems to involve excitement or risk, for example because it is to an unfamiliar place or because you are looking for a particular thing.

If a group of soldiers make a foray into enemy territory, they make a quick attack there, and then return to their own territory.