The following page of the FF7 Remake guide contains a walkthrough for Chadley's Report. This side quest is available in Chapter 3 - Home Sweet Slum.
Chadley is a young genius in Materia research. The boy will ask you to equip his Materia - Assess and get data on any two monsters. It is worth doing it as soon as possible because thanks to Assess you can e.g. learn how much HP a given monster has, their resistances, rewards for defeating them, etc.
Examine any two monsters and go back to Chadley. The boy will then start selling you new Materia - purchase Auto-Cure and give them to your companions so they will be able to heal you in combat. You will also receive 500 Gil as a reward for completing the mission.
That's not all, you unlock the Battle Intel tab, where you will receive special tasks from Chadley. You can meet the boy from time to time - complete Battle Intels to e.g. unlock new Materia, summons and other rewards.