Is it possible to have 2 4K screens with a MacBook Pro?

Officially:

• • It supports one screen at 4096-by-2160 (4K) resolution at 24Hz from the HDMI port.
  • and up to 2 displays at the 2560-by-1600 from the Thunderbolt ports.

MacBook Pro (Retina, 15-inch, Mid 2014) - Technical Specifications

But it's possible to get 2 monitors to run at 4K, though not both at 60hz. and it may have issues if both monitors are plugged into the Thunderbolt ports.

See here: Dual 4k support for MacBook Pro Mid 2014 - Apple Community

ulpe wrote:

Understand that, sorry, but bought it before 2015 and isn't sure exactly which Mac it is, except that it is MacBook Pro 15 inch.

The graphic card is Nvidia GeForce GT 750M and just wan't to know if it can handle to external 4k screens?

MacBook Pro (Retina, 15-inch, Mid 2014) - Apple Support

ulpe wrote:

Have a macbookpro with serialnr C**********D, is it possible to have 2 4K screens?

Never a good idea to publish your serial number in a public forum.

Maybe if you simply state what exact Mac is this...

>About this Mac <MacBook Pro 15-Inch "Core i7" 2.5 Mid-2014 >

Get help with video issues on external displays connected to your Mac - Apple Support
 https://support.apple.com/en-us/HT201177

Use multiple displays with your Mac

https://support.apple.com/guide/mac-help/use-multiple-displays-mchl7c7ebe08/mac

Using 4K displays, 5K displays, and Ultra HD TVs with your Mac - Apple Support
 https://support.apple.com/en-us/HT206587

Use the LG UltraFine 5K Display with your Mac or iPad Pro https://support.apple.com/en-us/HT210205

32-inch Retina 6K display https://www.apple.com/pro-display-xdr/

https://support.apple.com/kb/sp704?locale=en_US

Scroll down to the section about Graphics and Video Support.

Open the Apple Menu->About This Mac option and it will tell you what it is exactly. No guessing necessary.