A sheepsfoot, because its blunt rounded tip cannot easily stab what is behind the cut, and its straight edge makes controlled push cuts predictable. A modest drop point is the next best choice if you want a usable point. Avoid needle points, long clip points and anything large.
A sheepsfoot removes the point deliberately, which removes an entire category of accident. It is the pattern used on rescue and marine knives for exactly that reason.
The straight edge also behaves predictably: the whole edge contacts a flat surface at once, so cuts go where you put them.
If a beginner needs to pierce, a drop point in a modest size is the right compromise. The tip is broad and strong, it sits in your line of sight, and there is enough belly to slice properly.
Keep the blade under about three inches. Length adds leverage and reduces control.
Needle points, which break and stab. Long clip points, which put a fine tip a long way from the hand. And hawkbills, which pull material toward you.
Whatever the shape, keep it sharp. See can a dull knife be more dangerous.