New Speakers help Edifier s350db

Hi there new around here and to the daunting hi fi world.

I came across z when searching for new speakers for my PC. After watching his video on the Edifier s350db’s I was sold, however after I have watched more and more and dove deeper and deeper into the hifi world and sound quality I believe I’ve come across a few issues.

Unfortunately I went a cheap option on my motherboard and got a Gigabyte B450M-DS3H which unfortunately doesn’t have an optical output, which do my understanding helps drive a better sound quality.

I believe that I can use HDMI to a DAC or amp however my knowledge is lacking in these areas and the more I think I know about them the more it seems like I don’t!

Any help in this situation will be appreciated. Happy to send a couple hundred more if required, open to any suggestions for this setup, I would prefer to have a sub but that can come later if required. I will be using them to watch mainly plays lots of music and watch some movies on my TV (driven by my pc) thanks!