Console Developer Kits?

Good morning everyone. How are you doing today? I hope everything doing well today and tomorrow for you. I have a few questions that i hope someone can answer. I have been watching some tutorials and been practicing. My laptop is slow and outdated. But I’m building a computer(https://youtu.be/BtQih352lac), which hopefully should be enough. If things go will. I should learn enough by the summer. That i can make a small project that i can test it on my home consoles. The thing is, my friend told me i needed a dev kit in order to test my project on the consoles. After hours of google search, I’m a little bit confused. So my first question is what a Dev kit and is it important. And my last question is do i need a PS4, Xbox One, Nintendo Switch dev kits, to export games to a console or i don’t need it? Thank you in advance for answering my questions

By the way,one last question! Is this build enough to run UE4? https://youtu.be/BtQih352lac