Install Unity game engine and Visual studio. Also learn to go around the Unity editor and do some basic stuff.
Understand how scripting works in Unity. Unity uses custom C# classes, so learning about them is very important.
Come up with a game idea. You can't make a game if you don't know what to make. Remember your first game should be very simple and should have just one level.
Make you game assets ready. Game assets are the images, 3d models, sounds and more that you need for your game. There are lot of websites where you can get them for free.
Code your game's core mechanics. If your game is about a bug jumping on a wire, then making that jump mechanics is the first step.
Polish your core gameplay. Before you go on to make your game look great, it's important that your code is bug free and the game is enjoyable.
Game Menu. There should be a way for the users to navigate through your game and they should be able to restart the game once finished.
Playtest. Now you have a playable game that you can distribute. Share it with friends and family to get some feedback.
Promo graphics. If you want to publish your game on game stores, then you need to create images and screenshots for your game.
Publish your game. There are some game stores like itch.io, where you can publish your game for free. Publish your game and share it with the world.
You can get all the required resource to learn game development at VionixStudio for free.