Spine 3.6 is very old. Please note that the spine-unity 3.6 runtime is officially compatible only with Unity versions from 5.6 to 2018.2:
http://esotericsoftware.com/spine-unity-download#Older-Versions
You may run into many problems when using Unity 2021.3 with it.
If you really need to use this old spine-unity runtime version with it, we need more information about your problem than just two screenshots without any additional info. Please describe your problem in detail, mentioning the Spine components you're using, if the skeleton has multiple atlas pages, if you are using special blend modes in your skeleton, and so on.
