.............my keyboard which has a small round 5 pin connector has nowhere to go......
Your keyboard is an old-style PS/2 one and your new PC doesn't have a port for it.
There are PS/2-to-USB adapters available but on most systems they don't work reliably, and frequently they don't work at all. The other alternative is a converter but at those prices you may as well buy a new keyboard instead. Most of the time you'll find that they only work when Windows has booted up so your keyboard will never be able to get into the BIOS etc.
...what are the 2 blue USB ports with ss written on them
They're "super speed" AKA "USB 3" ports. They're backwards compatible so your current USB devices will work fine with them.