Tried to add text to the bottom part of the screen on main menu:

{
  "main_menu": {
    "top_left": [],
    "top_right": [],
    "bottom_left": ["VicoCraft 1.19.3-0.1 BETA"],
    "bottom_right": ["PS.: Contém BUGS!"],
    "mod_blacklist": []
  },
  "pause_menu": {
    "top_left": [],
    "top_right": [],
    "bottom_left": [],
    "bottom_right": [],
    "mod_blacklist": []
  }
}

But none of the lines appear (i though it was to appear above or below those lines).
Putting the text on top_left works as intented.

I simply use Minecraft's text parsing system. So you would do:

{"text":"VivoCraft 1.19.3-0.1 BETA","color":"red"}

You can also do click events as well:

{"text":"VivoCraft 1.19.3-0.1 BETA","clickEvent":{"action":"open_url","value":"https://vivocraft.net"}}

Sorry the insistence, but how is the proper way to add multi-colored lines via config?

I tried "bottom_left": ["\u00a76VicoCraft \u00a7f1.19.3-0.1 \u00a7cBETA"], although it worked clearly isn't the proper way (it needs to be JSON).

This is not the format for text.

{
  "main_menu": {
    "top_left": [],
    "top_right": [],
    "bottom_left": [{"text":"VicoCraft 1.19.3-0.1 BETA"}],
    "bottom_right": [{"text":"PS.: Contém BUGS!"}],
    "mod_blacklist": []
  },
  "pause_menu": {
    "top_left": [],
    "top_right": [],
    "bottom_left": [],
    "bottom_right": [],
    "mod_blacklist": []
  }
}

This is not the format for text.

{
  "main_menu": {
    "top_left": [],
    "top_right": [],
    "bottom_left": [{"text":"VicoCraft 1.19.3-0.1 BETA"}],
    "bottom_right": [{"text":"PS.: Contém BUGS!"}],
    "mod_blacklist": []
  },
  "pause_menu": {
    "top_left": [],
    "top_right": [],
    "bottom_left": [],
    "bottom_right": [],
    "mod_blacklist": []
  }
}

Strange. The JSON i was using worked fine on top left...
BTW, if the whole tellraw json is accepted, does it means i can set colors and formatting for each line? Can you give me an example, if possible?

This is the legacy way to colour text.

And what is the proper way to do that then?