To finish the game Hello Neighbor: Hide and Seek you have to recover the doll that your brother has taken away from you.
To find a doll you have to leave the house. To do this, run forward all the time after you leave the room. When you reach the stairs, climb them and turn around. You will see a trampoline there. Jump on it and this will allow you to get to the next part of the house.
Your next task will be to jump to the object shown on the screen above. It will knock you into the air. This will allow you to get to the next room.
Going further on the boards you will reach the exit from the house. There, use planks and chimneys to move on the roofs.
Use a ladder to get to the top of the roof. There, at the end - your doll is waiting for you.
When you pick up the doll, the game will end. You have completed Hello Neighbor: Hide and Seek.