it seems as though you already have your mind made up. so, out of respect im not going to convince you to change your mind. you're a grown as man, at the end of the day if you don't want to try and live anymore that is your decision.
A fentanyl overdose inside of a locked room is not only the most humane way to go out, it can offer relatives some amount of piece knowing you died with no pain. I have overdosed on fentanyl and died (i was dead for 35 seconds). There was no vision, no dream and i do not remember anything. 0 pain and i only vaguely remember falling out. Falling out is the sesation users get when an overdose goes into effect. It is eerily similar to faiting or being knocked out, except there is an overwhelming sense of euphoria. Downside is you die of course, and you sweat intensely before you fall out.
I have provided you this information with no opinion on your actions. I don't care if you live or die. However, my life has changed since my overdose. I have genuine friendships, i have repaired my broken bonds and i am thankful to be alive. That is just my experience.
Happy trails, traveler.