can i stack 8 switch witch stcak cable 50 cm?

Hey brother no offense, but this is not correct. It goes 1-2, 1-2, 1-2, First Switch Stack port 2 - Last Switch stack port 1. The correct cabling guidelines are found here: www.cisco.com/c/en/us/td/docs/switches/lan/catalyst3850/hardware/installation/guide/b_c3850_hig/b_c3850_hig_chapter_010.html

While you are creating a ring, you are doing it backwards to Cisco instructed documentation.

Nice work. Here is a guide of cisco 3850 switch, I hope it will help others. ciscodatasheet.blogspot.com/2017/08/cisco-catalyst-3850-series-switches-faq.html

Please also add video of configuration part..

thank you!