How to download life gen- full gen?

Hi all! I’m not very good at tech related stuff and I am having trouble downloading this file. I was able to find it on GitHub but I don’t know where to go from there. I saw someone say go to assets but there is no assets button for me! I don’t know if I’m looking in the wrong place but I don’t know where to start! Thank you and sorry if this is frequently asked!

Also, if anyone knows of a mod that has natural disasters or where it is harder for a clan to survive, can someone let me know? Thank you!