inclined slope question

The string is in tension, indicating that equal and opposite forces apply to it. Weight of the object (due to gravity) pulls down on the bottom of the string, while the force applied by the puller pulls upwards on the top of the string. This should clarify any ambiguity you have in relation to whether forces pull up versus down.

The diagonal force of the string can be decomposed into a horizontal and vertical component.

The directly downwards force of gravity and the diagonal force up directly out of the surface combine to precisely the equal magnitude and opposite direction to the force on the string.