My Bernese won’t settle

My German Shepherd cross Bernese Mountain Dog male puppy has just turned 12 weeks old (had him since 8 weeks), and I'm having trouble teaching him to settle on his bed. I read that you should drop treats between their paws to make them stay on their bed's, but now I feel like he won't calm down and is constantly looking to me for his next treat? How do I get him to stay calm on his bed? He is crate-trained and very good in his crate. Also, he is a total shark, we can't stroke him without him trying to bite us; I am using kong's, lick mats, chew toys but he just seems to not enjoy being stroked? Any advice please…