Its not the data or history on here that matters, they wont get into the site.
Its the computer and or devices you joined, browsed and acsessed the site from.
If your being investigated all you can do is make it more difficult for them, you cant actually completley erase.
You need a bit of time, get some paper and write everything down, all emails and accounts you have " allegedlly" partaken in criminal conduct.
Remembering that eroids is only a review site.
Anyway go through and manually delete everything from all those emails and accounts, remember to delete the trash/ junk/ spam.
Go to the account profile settings, block all incoming mail, now change you user name.
Example- name is john smith, change that to jane smith or what ever.
Change or upload a new profile picture, use the picture of a flag from another country.
Change all personal details such as location and date of birth, you likely need a text verification code to do so, thats fine, do that, make sure you are half an hours distance from you home residence when doing this.
Done all that now delete the accounts permanantly, again text verification or sometimes a waiting period, thats fine, do that.
Do that to every account/ email etc.
Next is your search provider- if its google you have a google dashboard, go through and delete all history from all time its one click, once thats done go through all the options and delete it all such as " other google activity" click on that make sure you erased that aswell.
Go through the entire dashboard make sure every option is deleted.
Do the same again on google, change name, picture, location personal details etc maybe text verification again do that, then permanantly delete your google account, this then double wipes anything you used on google.
Save your personal photos and whatever you want to keep from the device to somewhere then go ahead and wipe your phone, do a full factory data reset with no backup enabled.
That will wipe the entire history from that device on top of the manual deletions you already done, remembering you 30 mins minimum from your home.
Now take the simcard out and repeat the factory reset.
Now get rid of it, smash it up into bits and throw it in a lake or some kind of water.
Drive to another location away from your home and destroy the simcard, if you can burn it do that if not use scissors to snip it up into tiny slithers throw the slithers out the window in different spots, not together.
Its the same process with a computer with all the manual deleting then factory reset it then take that computer or laptop to destroy it and where it wont be found.
Computers obviously require more destroying, you really gotta fuck them up, put in a metal barrel and pour petrol on it, burn it and repeat, get the melted shit out of the barrel and chuck in water/ lake/ river/ sea.
The problem is devices constantly check locations in at nearest towers as you pass them.
They will know the location in which the devices were at particular times even if location was turned off they can get it, quickly these days aswell, sometimes sameday from phone companies, they cant find or get the devices, so they cant physically prove it was you on the device at particular times but they can get location logs and if there all from your house address its obvious to them, you can throw other spanners in to the work by saying you always suspected you were being hacked, you have lots of visitors using your computer, you didnt have locked wifi or password for mobile data and you think your neighbours kids and friends have been using yours, you cant say you lost your phone due to the phone logs and the phone location logs which are precise, with in 30metres of your home, of you lost them or they got stolen why would it still be at your home address.
Best thing to do is the above destroying and disposing and keep your mouth closed.
Say nothing, answer no questions about anything no matter how hard they press you or try tricking you.

We always preach on here leave no paper trail... we dont say it for fun, im assuming you have and thats why your worried about history.
If you get in this game, it starts the moment you start googling and searching on how to purchase steroids.
Always cover yourself.
Anyone reading thats new, remember that, your location is never private even if you think it is.

Good luck