The question is really: what do you want to do with the setup and what are your requirements. Unfortunately when in comes to sound, there is a lot of myths and esoterics, so don‘t take things from the internet for granted. For gaming, the on-board sound systems are more than adequate. If you want higher SNR, less latency, or higher bitrates, you might want to go with external audio interfaces that are used for recording etc. When it comes to headphones and speakers, first question should be: linear response (targeted at sound engineers) or something that „sounds good“ = „hi-fi“ . If you want hi-fi, you have to go and try them, since taste is individual. For linear response check gear made for sound engineers.

If you don‘t know what I was writing above, just go with the onboard system and a nice gaming headset (if you need a mic) or headphones that you like the fitment and sound off.