The oldschool days of game design are over and now things are easier than ever. A game engine takes all the diferent aspects of a game like graphics, sound, ect and puts them all together for you in one place. I can only really speak for Unity but Unreal is like 80% the same as Unity.

First off, if you're offput by the idea of programming, there are three solutions I have for you. 1: I use Playmaker. Yes it costs 65$ but it uses States ( lists of actions going top to bottom) and those actions can lead to other States using something called a Transition. 2: Unity has a free visual scripter like Playmaker called Bolt and there are apparently several others I can't vouche for but give them a try. 3: You can also have Chat GTP generate you a C# script but Unity has it's own AI tools for that now too.

Secondly, you're going to have a' scene view', which is what you see from a developer perspective,  as well as a 'game view' which is only what the player sees. You can easily spawn objects into the world but you need to tell Unity if that object uses physics by tossing on something called a Rigidbody component. It's a component that handles all physics for that object like it's mass, any contraints( doesn't go a certain direction, can't turna certain direction), does it use gravity, ect. Attaching components is as simple as clicking on the object and going to "Add Component". It couldn't be easier.

After that we have Colliders. Those tell Unity if an object has a physical boundary or not. Unity, and most game engines, have colliders that are basic geometrical shapes or will be generated based on how an object looks (its appearance is called its 'mesh'). If you just want an object to be a graphic, then get rid of the collider. If you want an object to be slippery or bouncy, you'll need a Physics Material, which is something you literaly just right click and create then change it's variables for whatever you want. Honestly these first bits are enough for you to put objects on a screen and watch them collide and roll. 

Your User Interface, UI, is pretty straight-forward. You make something called a canvas, and this is just like a painting canvas and you can put it in the world freely, or have it glued to your camera the player sees from. There's a wonderful object for your UI called Raw Image which lets you pretty much put any picture you have on there.

Then we got textures and honestly you can draw something in paint, save it as an image, import it into Unity and slap it onto something. If you have Gimp or something else, you can easily use that. After you make a texture, you can choose a scale mode and move it around an object to get it just right. 

For animations, you can go to Mixamo.com, completely free and download both whatever animations you want and what characters to use them with. Unity has something called an Animator, which is essentially a pack of whatever anmations you put into it that you toss onto your character then you tell Unity which animations to play and when.

For cool effects, like explosions or lightning, you have Particle Systems. They generate particles and let me tell you, Particle System addiction is a real thing. You can spend hours just screwing with it. It's all super easy to understand settings but they let you make almost any effect you want. A PS just spawns particles. you can change the shape and way they spawn, the amount, the look and color themselves, how long they live for, what direction and even put in fields that pull/push them in a variety of ways!

Then you have the cherry on top: the Unity Asset Store. An asset is anything in your game. It can be a script, a physical object, light settings, an add on, anything. There's more than enough free stuff too.  I've spent hours browsing the asset store. There's almost something for everything. The other cool thing with that store, is it lets people sell their creations so if you're a 3D modeler, you can make something cool, toss it up and make money on every purchase!

Here's a link to making your first game where you just dodge objects and navigate a level. Super easy but also highly modifiable for whatever you want.