Here I'll tell you:
https://thenewamerican.com/un-agenda-2030-a-recipe-for-global-socialism/
Basically they'll take away most of what makes life worth living and then after a few generations you won't even know it, and you'll be happy. No more cars, planes, or trains. No more farming or jobs. You'll sit in your home and stare at the TV eating toxic rations given to you by the government.
https://www.heritage.org/environment/report/consequences-paris-protocol-devastating-economic-costs-essentially-zero
Most US businesses and cheap energy would be shut down. Rolling blackouts for weeks at a time, etc...etc...