CrossFit for Beginners?

I'm looking at possibly getting into crossfit. I have 50+ lbs to lose and am 46 years old, I'm working on my nutrition but wanted to know if crossfit would be a good fit for me. I have never done anything like it before and don't consider myself any kind of athlete. I have done work out classes before but nothing that pushed me into extreme fitness levels. How does crossfit work? I know everyday is different which is what has enticed me, I don't want to get bored. What does a typical class look like? Is it super intense every time? Can anyone give me some insights? Will crossfit help with weight loss? (aside from nutrition) TIA