Europe had practical seafaring since antiquity. European naval technology during the discovery of the Americas was on par with other Eastern Hemisphere naval powers.

No and no. In antiquity they followed the coasts most of the time, and followed really safe routes across mostly-closed seas the rest of the time. Trireme construction was good enough to take rough weather, while it existed, but for one thing they had trouble with navigation.

Chinese boats of the early modern era were leaky and unseaworthy by comparison, if sometimes extremely large for show, and their sails didn't tack nearly as well.

The Vikings did manage seafaring, but they had a very specific design that was pushed pretty much to it's limits. You can't make a clinker-built longship any bigger or better really, and eventually economic conditions meant they stopped bothering with the big expeditions. Later on some of those same techniques made their way into the caravel.

The Polynesians managed it much earlier, and did spread around, but they were otherwise in the literal stone age. It is still pretty curious they didn't leave more impact on the Americas.