Favorite resources?

Hi everyone, I had a family member diagnosed with colorectal cancer pretty recently and our whole family is just trying to process. I've tried researching but there is just so much info out there...

Would our whole family have to get tested now? Did you change your eating habits after getting diagnosed and what else do you have to change? Should you always get a second opinion? Anything else you think we should know?

I'd appreciate you sharing your favorite resources that worked for you personally.

Thank you