What is the best way to rig a 3d character and inverse kinematics now?

Question

3D

What program is currently the most relevant for creating rigs and inverse kinematics (so far I find the most information on Blender)? All this is needed for subsequent use in Unity. And advise more articles / lessons on this topic, where exactly the basics are understood. What bones are needed when, how to set up the kinematics correctly, and so on.
PS As I just found out, blender cannot export inverse kinematics (constraints- and IK-bones) to FBX. And all this only works because Unity creates its own kinematics for the human rig. OK. And if I have a spider rig, for example, what should I do?

Answer 1

https://www.mixamo.com - you can try.
In general, Blender is also normal, and there will be more tutorials on the network for it.

Answer 2

Blender is free. And so all popular packages can export to files with the .FBX extension - this is the standard format for storing skeletal characters and not only for Unity and Unreal engine.
In general, you can use whatever you like from 3ds Max, Maya, Blender.