First, scene safety. If there are any IMMEDIATE threats (wounds that need treating, potentially injurious situations), deal with them.

After that, Stop, Think, Observe, and Plan.

If there's a working communication device (PLB, SEND, cellphone with signal, radio) it's time to start signalling for help.

Staying put or moving is going to be a decision based on shelter, water (and possibly food) availability, my physical condition, the clothing and particularly footwear available, tools and the rest. If I'm uninjured, wearing clothing and footwear appropriate for the environment, there are no resources nearby, and immediately find signs of human habitation, I'm almost certainly going to attempt to self-rescue.

If I'm hurt (particularly in the legs or feet), barefoot, need to build shelter immediately to survive, there are lots of resources nearby, and see no signs of human habitation, I'm almost certainly going to stay put and do what I can to make myself visible and safe.

In an in-between situation my inclination would be towards building a reasonably-sustainable shelter, collect resources, and consider moving to terrain that gives me a better view of the surrounding area and see if self-rescue could be a viable option.