Video games are made from many constituent assets. It is common to have staff assigned to creating only one type of asset, as, a wide range of skills ans software are specific to different assets.
Sprites are 2D graphics, usually for a character that can be animated using a sprite sheet.
We can produce these using Affinity Photo or Designer
Backgrounds are larger drawings loaded into memory
We can produce these in Affinity Photo
UI ( User Interface )
This is includes Menu Items and HUD ( Heads Up Display ) elements.
Examples include health bars and onscreen maps
We can produce these in Affinity Photo and Designer
Three dimensional models are usually used for characters, items and environments.
We can create these in Blender
Textures are the flat graphics applied to 3D Models in order to give the colour. These graphics usually appeared stretched due to a process called UV wrapping.
We can create these in Affinity Photo
Music is simply the music played in a game - it is common for game music to be endlessly looped, or to have multiple layers than can be mixed in depending on the player situation.
Full audio tracks can be used, however midi music will drastically reduce file size.
We can create music in Reaper
SFX ( Sound effects )
Sounds effects are short noise that are usually play in response to a player action.
Again, these can be created in Reaper
Vocal performance is usually lines of dialogue delivered by the characters in game.
Using a microphone, we can record our own dialogue.
Text files in games can be used to store all types of data. For this task we are only concern with text that will be shown on screen - usually when interacting with an NPC ( Non-playable Character )
Sky boxes are usually textured geometry floating above a 3D environment, that give the impression that there is a sky above.
You can store videos inside your game data - this would normally be to playback a story Cinematic. These are often out-sourced.
Videos can be created in DaVinci Resolve and Blender
In 3D games, character usually have a standardized skeleton. This means that skeletal animation data can be saved separately and transposed onto multiple characters
We can produce skeletal animation data inside Blender
There are a number of ways to legally source assets, these include, but are not limited to
Each of the above methods still have copyright implications - however will be fine for personal work.