Statistical inference is simply
The process of drawing conclusions about a population on the basis of
measurements or observations made on a sample of individuals from the
population.
as defined in Cambridge Dictionary of Statistics by B. S. Everitt. It is close to the general definition of inference, i.e. "act or process of deriving logical conclusions from premises", or "observation of patterns of facts, to see new meanings and contexts for understanding indirectly" (see also here, or here). List of all the possible approaches to statistical inference for all the possible statistical problems is unlimited.