What breakpoints to use?

Question

Layout

Hello!

In general, you already know the question, please tell me 1. Which breakpoints are the most popular and which ones do you use most often and for which devices?
2. And also, is it worth making an adaptive for large monitors like 2560x1440 - 3840x2160 (4K), in general, the site looks good on large monitors, but some elements are stretched and the sizes are relatively small?

PS I recently completed my flexbox training and the adaptive began to work out, so I want to make layout for all devices!