Hot to contact FB Group members?

Hello Guys,

I'm selling social media services and i have problems finding a possibility to contact all members of some targeted facebook groups..

Beeing able to contact them outside of facebook would be great (email ect.) but if its not possible i would do it via facebook messanger, in case they get the message not as spam ..
Do you think that facebook would take further "Law-steps" against me when they get me in their focus?

You Guys certainly can provide me some help

Thank you

Greetings

Facebook doesn't have time for these things to take legal actions for these things , they just simply ban the account.