This is education, not advice
The information here is written for the general reader and does not replace a personal medical consultation. It cannot tell you what the lesion on your skin is, whether light treatment is appropriate for it, or how your skin type will respond.
No outcome is guaranteed
No treatment can be guaranteed. How much pigment or redness improves, how long the change holds, and how the skin settles afterwards vary between individuals, and a result is judged honestly only after the skin has had time to settle.
Results are not permanent
Neither broadband light nor a picosecond laser stops the process that produced the problem. Sun-related pigment and redness can return, hormonal pigment returns most readily of all, and maintenance sessions and daily sun protection are part of how a result is held rather than optional additions.
The risks are real for both
Either light source can leave the treated area darker or lighter than it was, can burn or blister if settings do not match the skin, and carries a small risk of scarring. Pigmentary change is a recognised risk rather than a rare accident, and it is why assessment comes before treatment.