One thing to keep in mind is whether the Surface has an Intel processor or the relatively new ARM Snapdragon processor. The Surface product line includes computers that use one or the other.
If it uses an Intel processor, you should be able to run the full Windows version of Photoshop, with no missing features.
If it uses an ARM processor, it will run the ARM version of Windows. Although Windows Photoshop does run on it, some features are not available on ARM yet. It will be a lot closer to what you want, it won’t be missing as many features of the iPad version, but for now it won’t have all of the features you would normally get running Photoshop on an Intel-based Windows PC or on an Apple Silicon-based Mac.
More info from Adobe about Photoshop on Windows for ARM, with list of missing features and known issues:
https://helpx.adobe.com/photoshop/kb/windows-arm-support.html
If nothing in that article is a problem for you, then you could be OK using Photoshop on a Surface Pro with an ARM processor. But if you’re not comfortable with the limitations, you might look for an Intel-based Windows tablet PC whether from Microsoft or another company. (I’m a Mac user, but Apple doesn’t make any tablet Macs.)
The iPad version of Photoshop is similar to the version of Photoshop that runs in a web browser.