Maybe, but you probably would have the best odds of not being found in the winter time, since your body would be covered in snow and by the time the weather heated up, your body would be decomposed enough to not be as noticeable. If you plan on taking pills and alcohol you could always try drowning by weighing yourself down, although there's always a chance the body could rise to the surface, but on the plus side you would be even more decomposed than on land if you don't want to be identifiable. The more dense the forest is, the better. You could also try an abandoned building.
The best place to go would be here:
https://en.wikipedia.org/wiki/Aokigahara
It's one of the most popular suicide spots because the forest is so dense and people know they won't be found.
It would be nice if when we died, our bodies just evaporated instead of being left here to rot away.