The laptop will support a 4K monitor
https://jcutrer.com/advise/products/dell-xps15-five-reasons-why-1080p
it has I think a 1050
https://www.nvidia.com/en-gb/geforce/products/10series/geforce-gtx-1050/
If the graphics card in the laptop cannot display 4K resolution then a 4K monitor cannot
https://jcutrer.com/advise/products/dell-xps15-five-reasons-why-1080p
it has I think a 1050
https://www.nvidia.com/en-gb/geforce/products/10series/geforce-gtx-1050/
If the graphics card in the laptop cannot display 4K resolution then a 4K monitor cannot