A floor pump with a pressure gauge, tire levers, and a set of Allen/hex wrenches (typically 2mm–8mm).

Solid bicycle repair and maintenance is about catching small issues before they become expensive (or dangerous) problems. By following a structured routine and having a few key tools on hand, you can handle about 90% of your bike's needs at home. 1. Essential Tool Kit

Rags, brushes (old toothbrushes work well), dish soap, and a dedicated drivetrain degreaser.