Bf said I'm not a good kisser... lol

So im not a good kisser. I was told this a while ago and I was super embarrassed and I didn't want to try and kiss anymore.

So now I don't really kiss that much because I don't really know what to do.

I have a very slight underbite that I'm going to get fixed but I think that is part of it.

Anyways does anyone have advice for me ? I don't use too much tongue and I don't 'eat their face' i don't think so its not that lol