how to install forge to at launcher vanilla minecraft

Overwriting is necessary because many mods write additional files into the world folder, and your vanilla world won't have them. This will collide with the existing world folder in the forge server directory, and you should tell it to overwrite existing files. Copy(NOT MOVE) the world folder from your vanilla server to your forge server directory.On the Forge server Copy(NOT MOVE, NOT RENAME) the world folder to world.forge.stop here, what you are wanting to do won't work. If a forge world can't survive this, then there is no way that your vanilla world will. If the world is corrupted, then the one of the mods you added will broke the forge world.In particular travel and look for chunk generation errors between chunks generated in step 4, and new chunks. test the mods, and visit all vanilla places that you went to previously. Try out blocks from the mods, go to their dimensions, etc. Start up your forge server and log in.choose carefully the more you add, the more risk that this will fail) Add any mods (this is the only time you should add mods.Start up your forge server and log in to it to verify it works (and generate a default world) - Go to the end and nether to generate them.Setup forge in a NEW folder (not covered here there are many tutorials online).Download the version of forge that matches your existing server's Minecraft version.Don't backup just the world folder, backup the whole server folder. Backup your entire vanilla server Really really dont skip this.This test is not perfect, but will get most cases. Below are instructions to test the mods to see if they will corrupt stuff by changing IDs. If you try this, make backups before starting.

Mods change block/dimension/item IDs and will very likely corrupt your world. What you are asking seems simple enough from a user perspective but is super complex under the hood. If you want to install forge, then I'm assuming it is so you can install one or more mods.From a technical perspective, there are a ton of things that can go wrong.

How to install forge to at launcher vanilla minecraft