1) How do I access the darknet?
2) How do I use it safely, since I wouldn't want malicious users to exploit my machine.
3) How do I find the information I need there. I need to write on cyber crimes and hacking attempts, possibly before they happen...
LoyceV has already provided you with good initial references for points 1) and 2).
Point 3) will be a challenge for you. Especially considering the questions from the first two points.
While I cannot tell what exactly your client expects from you, if I were you, I would suggest they find another person to complete the job.
I prefer learning how people find what they're searching for there. Seems there are opportunities to learn a lot down there. If I can find out how searches are conducted in the darknet, I'll pull this off.
@Loyce, thanks for your input. I already got the Tor aspect.