This is a great place for that kind of help. I'll go over a few basic pointers to get you started. I will also include links at the bottom for all the free programs.
For one you will need a engine to make your game and tell your story. The most popular; is Ren'Py.
There are other engines such as Twine, but I think Ren'Py would suit you best. You do not need to learn any code in Ren'Py. Ren'Py dose use a simple script for basic things, you can also use Python with it. Do not let code scare you, code is not hard to learn. Ren'Py is 2D because it uses pictures, it also supports animation in the form of OGG Theora, VP9, VP8, MPEG 4, MPEG 2, MPEG 1 files.
Then you will need visuals, there are many ways to go about this from 3D to hand-drawn art. From the 2D side or hand-drawn, you could use things such as Photoshop, Gimp or Krita. From 3D you could use Blender - In this; you will have to make everything from scratch, nothing is made for you. Daz3D - This is best and is what a lot of people use, has premade characters, clothes, hair, etc, but you will notice that if you want something new you have to make it your self or buy it off the market. Thankfully f95Zone is here and has a
Asset Releases section with all the pirated good stuff. Then you also have Honey Select; It's already a game but it has a studio version that is kind of like Daz3D, but is uses it's own characters that you can customize.
Most VNs will use: Ren'Py and Daz3D (there are quite a bit that use Honey Select too.)
If this post did not help at all there is a guide on this site that gives you all the links you could ever ask for.
Link
Game Engines
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3D Art
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Honey Select
2D Art
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