The brain system that provides temporary holding and processing of information to accomplish complex cognitive tasks such as language comprehension, learning and reasoning, and holds the information you are focusing on at a given moment, is

Working memory is the brain system that temporarily holds and processes information to carry out complex cognitive tasks like comprehension, learning and reasoning, keeping in focus what you attend to at a moment.

Its defining feature is active manipulation of information, not just storage.

Episodic memory stores personally experienced events with their time and place, a long-term form.

Semantic memory stores general facts, concepts and word meanings in the long term.

Short-term memory holds information briefly but is largely passive, without the processing working memory adds.

The working memory model was proposed by Baddeley and Hitch with its central executive and slave systems.