"For some reason i cant access it":
1. Click this: https://bowlroll.net/file/176844
2. Copy and paste the entire Japanese text into google translate

"I dunno what they mean with the password":
1. Learn EVERYTHING about Black Lagoon: https://en.wikipedia.org/wiki/Black_Lagoon (read the manga, watch the anime, read the wiki, etc).
2. Google translate the password hint: http://www.nicovideo.jp/watch/sm33250046

(Note: No.1 comes before No. 2, right?)

You can't access the second link (Dark Magician Girl model link) bc either you aren't logged in bowlroll or your settings there are blocking R-18 tagged content.

the password is the alias of levy in the anime but written in kanji
lately they put password with Kanji script, this is annoying.

Here I leave the link where is the answer
http://quizn.jp/quizresult.php?quiz_no=21007&choices=1

@FireManHawk then it's your settings in bowlroll lmao, change them here https://bowlroll.net/home/edit
it should look like this to display R-18 tagged files https://i.gyazo.com/d60e00010c09a8eb1786dc9d2d4d7b93.png

If I already test the password and it works, I will describe the model.

"Please tell me the password for Revy model"

I have good knowledge of the Japanese language and zero knowledge of Black Lagoon.

Zero knowledge = no idea about the password :)

Here is what you need to identify kanji characters seen on-screen in an anime: http://classic.jisho.org/kanji/radicals/ Just click on each kanji radical you are able to identify in the kanji seen on-screen. The kanji suggestions at the bottom will become fewer as you click on more and more radicals. (This method is quicker than using OCR software on screendumps, I guess? It's certainly better, because you'll learn something about kanji in the process.)
(After a while you'll recall radicals by position. And then it's annoying that the line breaks depend on the windows size. So first of all, I always adjust the window size so I get 匕 in the upper right corner, so I get the radicals in the positions I'm used to.).

but that's the way you ask for help, you'll receive a lot of advice, if it works out, that's up to you.
I pass the link where the password is, it was just copy the answer 2 and you can download your model.

Removed

here is the password 二挺拳銃, copy and paste

for the second you have to have activated in your account the red box show adult content and so you can download the content r18