Pokémon yellow from 3Ds on emulator?

Is it possible to bring Pokémon yellow from 3ds to laptop (with emulator) if so how?

and would that be legal?

You mean you bought this on your 3DS? Then yes. Is legal.

To copy you first need a custom firmware. Start with that first.

And that won't be published automatically either?

What do you mean "automatically published"?

What to publish it illegally I'm afraid that the emulator will publish it automatically

If you copy the game on your own, you are not committing a crime. Nobody will put any punishment on you.

Ok, do you know what boot.firm is?

Boot.firm is the file that Boot9Strap loads. It contains all patches for the custom firmware, e.g. To be able to install your own apps in the home menu.

You can download the yellow edition of Rome right away

Illegal

And is it really all legal?