A quick way to get the idea I wish to indicate by "instinct" is to imagine them as like the programmed, un-learned, capabilities of a robot. Then, we can go further ...

An instinct, B, can have its behavior, Behavior(B) and its releasing or guiding stimulus, represented in the number Conditions(B). A number, Urge(B), determines the priority of B relative to other behaviors the animal (or robot) might be doing. And there might be other instincts that facilitate or are facilitated by B. The expression of B in an individual can be shaped by factors, such as past experience, that are peculiar to that individual.
In robotics, one can solve the problem of "what to do next?" by computing, perhaps several times a second, for each programmed behavior B a number

Urge(B) = Drive(B) * Conditions(B).

Konrad Lorenz has provided examples of inter-related instinctive drive mechanisms in animals.

Miscellaneous example of a set of possible instincts:
There might be three or more instincts related to walking.
A) An elephant has instincts for walking. You can imagine that an elephant might walk alone on some mission of its own (maybe to check out the vegetation over yonder).
B) Elephants also might walk together in a family group. They do so in such a way that the group remains within a circle of some radius, able to hear and warn and inform and support one another. Walking in a family group has an instinctive basis.
C) Elephants can, maintaining proximity to family members, move as part of a herd of families in, for example, a migration.

I assume that, properly understood, human behavior is founded on instincts, possibly thousands of them, as yet undiscovered.

Social Mitosis ("aposyndesis")