How to install a larger screen on the MacBook Neo?

You cannot install a larger screen in the MacBook Neo chassis itself.

You can attach one external display with a resolution up to 4K and a refresh rate ip to 60 Hz. The MacBook Nro has two USB-C ports. One supports USB 3, DisplayPort, and charging; while the other just supports USB 2 and charging.

There are many 4K monitors on the market with screen sizes of 27” or even 32”. You can get adapters to go from USB-C (DisplayPort() to plain DisplayPort or to HDMI. However, since the MacBook Nro does not support Thunderbolt, you cannot use monitors which require it.

If you wish a screen larger than the 13-inch one that the MacBook Neo is built with, your options are to connect an external monitor as our friend @Servant of Cats has suggested, or buy a MacBook Air or MacBook Pro with a larger built in monitor. Seemples!