First, he's pushing for public ownership of several major businesses/assets and I suspect he wouldn't stop with the ones he listed. I don't mean to be that guy but that's full on communism, which has a long history of failure. I can't begin to explain why in a single post, there is lots of literature on it.
His entire approach is to take from the rich and give to the poor - and that's not entirely a bad thing. The problem is that's ALL he has. It won't solve the problems we have.
Prices are set by supply and demand. When people have more money, the demand effectively goes up and actually increases prices. The solution is to increase the supply, witch he doesn't address at all for things like gas and groceries.
He has absolutely nothing for stimulating the economy, or making us less dependent on the US.
He keeps saying we need to be creative but he's just rehashing old ideas that were proven to fail.