Sometimes I just like having ultra crispy experiences, so I like to play the oldest and clunkiest version of games possible. apparently, there was a dosbox version of fallout 1 so I#m definetly going to be trying that out.
I found this old thread http://www.abandonia.com/vbullet/showthread.php?t=26128 which seems to be very usefull, the only link that won't work anymore is the link to the 1.1 dos patch, but a quick duckduckgo search lead me to this https://www.nma-fallout.com/resources/fallout-official-v1-1-patch-dos.49/ .
I'm only using the digital version downloaded from gogf, I don't have any cd or anything and am trying to run it on the latest version of dosbox.
dosbox shows a loading screen but after the loading it just goes into a black screen without any sounds

What is wrong with playing the game with the DOSBox bundled with the game or installing the GOG version and then replace the DOSBox found in the game's folder with the latest DOSBox version, if you want the latest?

You obviosly made something wrong during DOSbox setup, if game launch ends with a black screen.

But I'd strongly advice you against using the official US patch v1.1 with GOG's stripped down EU v1.2 trilingual game distribution. It's not the clanckiest or oldest version you get, it's unpredictably buggy mess with possibly broken saved games.
GOG too made this amateurish error while providing engine v1.1 along with it's digital game as a 'classic Fallout'.

Tell us clearly and simply first what exactly do you want to achive?

1. US, EU/UK and GR version of the game have different levels of censorship. If you are from Germany, AFAIR, even on GOG you get the worst possible cut down edition. But the original was the US release, so in terms of cut out content it is the best.

2. There were three definite version of Fallout: 1.0, 1.1, 1.2. The 'clanckiest' and the most bugged one would be 1.0. Not 1.1 or later. Anyway both 1.0 and 1.1 existed only as a US disk release (actually as Australian too). All European releases has version 1.2. And all digital distributions are based on it.
So, the only way to get 'the clanckiest' experience is either to own an older disk release or get it from one of the "bad sites". Because it's not enogh to just replace an executable and dozen of scripts to downgrade properly. If you are interested I can provide xdelta patches, though, to downgrade data files.

But, again, what do you want to achive exactly?

just playing the game in dosbox

Ok. And you have digital version of the game you bought from GOG. Which language your game has? Is it Deutch or English?

english