How much paper will be needed to cover a triangular prism shown?

Answer 1

The "shown" triangular prism does not exist as none is shown, therefore no paper will be needed to cover it.

This is impossible to answer without the "shown" prism. You will need to re-ask the question including the dimensions of the prism, in which case you are really asking for its surface area; this can be calculated:

Twice the area of the triangular ends plus the perimeter of the triangular ends times the distance between the ends:

surface_area = base_of_end x height_of_end + perimeter_of_end x distance_between_ends

(note: area of triangle is 1/2 base x height, but there are two of them so this becomes 2 x 1/2 x base x height = base x height).