Peeps need PATHS to access rides and other buildings.
To place a path, tap on the PATH MENU to open it.
Simply trace a path with your finger, to CONNECT THE PARK ENTRANCE to the placed item.
To move the camera, select the CAMERA tool. You can drag, zoom and rotate around.
To erase a path, select the EREASE button, and trace with your finger on path tile. 

You can change the color of the path, by pressing on the yellow arrow over the path tool and selecting another color. You can trace on the ground or on already placed paths. You can also re-color the entrance tiles that are inside the park.