How to confirm how many peers a node has? When a node requests one of it's neighbours for a list of it's peers, that node responds with a list of all of it's neighbours. I'm just wondering is there a way to confirm that those nodes are actually his neighbours and not random/bad nodes?

Or is there an easier way to determine which of your neighbours is the most connected i.e has the most connections to it?
When a node requests one of it's neighbours for a list of it's peers, that node responds with a list of all of it's neighbours.


No it doesn't. It responds with list of nodes that its aware of being claimed exist.  It likely isn't connected to any of the nodes it returns and probably has never connected to many of them. Many of them may not even be real. (though some of them will be, because it does make an effort to include at least some that it has previously connected to)

There is no direct way to get information about a node's peers, and ways to do so are considered a security compromise (if not the most cosmically critical one).