strange editor behavior

as you can see on the fictures i’m not able to get near object because they just disapear however i can still select them i know i problaby did something in the editor but can someone tell me how do undo it cause it’s really frustrating
i’m using windows 10 Pro 64bit

This is happening because the camera is zooming (Wheel mouse), which will cause clipping at some point. Instead of zooming the camera’s view, just move the camera closer (Right Click + WASD).

Double click on an object in the Hierarchy, this will make the camera focus that object. Use Right Click + WASD to move around. Alt + Left Click will rotate the camera.