What do you have to do to watch YouTube videos in 4K on the laptop? Does that make any sense?
Your monitor in notebook must be able to display 4k.
Whether this makes sense is a question of the monitor size.
It depends on what your laptop can represent for a resolution. If you don't have a 4k screen, YouTube can't display it and scales it down to the corresponding value. In addition, most videos are only published or recorded on Full HD, i.e. 1080p.
If your laptop can only handle Full HD resolution, 4K is of little use to you. You wouldn't notice any real difference to Full HD. You can set the resolution for the respective YouTube videos that were also uploaded in this resolution.
Your monitor must be 4k capable
And good internet
Your laptop must be able to 4K otherwise the whole thing won't work.
