That's a DAC iirc? Generally no, Dacs only support 1 input source. Some can output to multiple sources depending on the model, but you're only getting your audio from 1 source at a time at any given point.
DACs can support multiple inputs and outputs. That said, they can only convert one audio source at a time. It looks like this DAC is USB powered, so you'll need to connect it to USB power regardless. Often, the DAC will choose one input as the primary and one as the secondary if more than one source is connected, and it will only convert the primary. Play around with it and see what works and what doesn't. You won't break the DAC. Alternatively, you could take a look at the manual.
It is expensive. You can get a starter audiophile headphone stack for not too much more. If you're looking to get into the world of higher-end headphones, for $200, you can get the Schitt Magni and Schitt Modi, or you can look into the objective 2/ODAC combo. Unless there's some killer feature that the SB X G6 comes with that nothing else on the market can do, I'd steer clear of it and stick to more reputable audiophile brands.
It creative's I'm not looking for high end headphone per say Just looking to improve my home theater set up and pc speaker