Character in Blender without modeling

This is the perhaps fastest and easiest way.
But it also comes with come downsides like there is no possibility for customization.
You also need to be careful under which license those are published if you want to use it in a project you want to publish yourself or even sell it like an Indie Game.
Some Characters are even modeled after existing characters like SpongeBob, in this case there is also a third party which holds rights to the Character as long as they are not in the Public Domain like Sherlock Holmes o Frankenstein.

Character Creator by Reallusion (which also created the popular 2D Animation Software “Cartoon Animatior” and the popular Motion capturing Software “iClone“) is a Software, which allows you, to Create, Modify and Animate 3D Characters in a variety of styles relatively easy.

There is also a Blender Add-on available which can import the Character in Blender fully textures and rigged.

Overall, it is a great piece of Software. The only downside is, that it costs $299 which is an extremely fairy price for such a piece of Software but for a lot of beginners this will exclude this option.

There are many styles, which are fairly simple to create, like a low Poly style or a Minecraft animation. And there are also a ton of Tutorials for those styles.
This is an example of an Animation I did a long time ago in the Minecraft style.
I think looking back, one of the best benefits of stylized work is, that it ages very well.

Also if you decide to take the stylized rout you maybe can take something away from this article: 8 Tips for better Low Poly Renderings

Human Generator is an Add-on which allows you, to create Characters directly in Blender.
It also has a lot of Options for customization, of course way less, than Reallusions Character Creator, but therefor it is way simpler and easier to use and also with $68 for a personal license or $128 for a commercial license way cheaper.

Mixamo is a free Online platform, which allows you to either pick premade Characters or upload self-made characters and rig them automatically, and add premade Animations to it.
Which allows you, to create character animations really fast like this one I made within a few minutes.