Well there are at least two programs you would need: a render or art program, and a game-engine.
For render programs Daz is the most popular one; You download assets (like characters, rooms, etc.) and load them into Daz to make your scene. You can find a good amount of pirated assets to get you going in the asset release section on this site, (it will cost you a lot otherwise). Its still advised to mix assets together (like hair from one on the other), and/or use morph packages (sliders which change the size of a body part) to create characters that are at least a bit different then 90% of the games posted here.
Blender is another render option. It has a steep learning curve, but in the long run you can get better results then Daz. The main disadvantage compared to Daz is you got to do some 3d modelling, texturing, and rigging (adding bones to your character so you can put her in different poses) before you can create your scene. It allows for much more freedom compared to DAZ. People that use blender often start with a Daz model, morph it around to create the look they want, and then go forward with creating skin, hair, and rigging the character.
It requires a fair amount of work to get started, but in the long run it can be worth it. You are much more free in how you scene looks like (in daz you are pretty much reliant on other peoples work), and how characters look like (same as before for Daz). Blender has a better rendering engine, and if your interested in animations blender is 100 times better then Daz for that (Daz can do animations, but is in general not advised do do that)
Outside of rendering to create your art, you could draw your own art, in photoshop or GIMP (the free photoshop version). This can make your game look unique compared to everything ells for sure, but isnt really feasible if you cant draw to start with.
Lastly Honey select is used here and there, but apparently the creater of that program stated a couple weeks ago, its not supposed to be used to create scenes for commercial use, so I would advise just to steer away from that one.
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Onto game-engines.
The main one used on here in Renpy. Its a visual novel game engine. It mainly just put text on top of pictures to get a story you click through. You can create different dialog options, and different paths, add some mini-games if you know hot to program a bit, but thats it really. Its great for what it does (creating visual novels), but nothing ells really.
RPGmaker is properly the second most used one, but has a bit of negative stigma. Fair amount of the games created by RPGmaker are just visual novels with a lot of walking between scenes. Most of them use the basic sets as well, so they all look the same. RPGmaker games can be good, but it should make sense why you picked that engine over Renpy; aka it has to be a RPG game. It doesnt mean you need to have a battle system (I prefer games without one, as 99 out of 100 battle systems are just easy spam 1 ability grind fests), but you need some parts of a RPG game, like puzzles, meaningful exploration, free-roaming, etc.
Unity is the third option, and is the most professional one by far. You can create whatever you want in Unity (mayor AAA titles use this engine as well), but it has a steep learning curve, requires you to know how to program, and in general just takes much longer. It has the most flexibility in what you can achieve, but requires the most dedication as well.
There are of course many more engines, but these 3 are the main ones (or pretty much the only ones) used on here.