From the battery icon on the screen grab, we are looking at a laptop, so a 17inch screen tops, and possibly just 13 inch. I wonder if the biggest selling point for the OP were all those tinypixels, or the fact that it was made of wood?
Blimey. Pasting the OP's screen grab into Photoshop revealed it to be a whopping 3200 x 1800 pixels, so something like this:
1. You have a "high dpi" screen. The advantages to this are that things that are painted on the screen in a reasonable size will be made up of a lot of pixels, and will be very crisp and clean looking.
2. Photoshop has not yet embraced "high dpi" operation. It's complex to do so, in that Adobe has to rewrite the software for all the controls on the screen to be able to use more pixels. That's not to say it's impossible, it's actually fairly straightforward for a given control - but there are a HUGE number of controls in many, many different places in the application.
Adobe has said they're working on it, and have made some noise about Microsoft not having supplied everything they need to succeed at the full reimplementation. But the current version does not have the ability to size itself up to be a reasonable size on your "high dpi" display.
That said, if you really, really want Photoshop to be "magnified up" to where all the controls (AND the pixels in the image you're editing) are much larger on your display, there is a workaround/hack... It's a bit geeky and requires registry editing, and one day when Photoshop really does gain "high dpi" support you'll need to remove the hack, but here it is:
I can't vouch for its performance, but it might make it usable for you in the interim.