How to do this?

Moderators, correct me please if something is not correctly written

Hi everybody! I want your help! See, I want to do such a thing as the telegram web version, toist, I choose with whom I want to chat and he shows me the message in the right box and in the address bar, the user name is appended with whom he will correspond, will show on this picture
See, if you click on the user (blue outline) in the right side (red outline) will appear in correspondence, and in the address bar, this will be the default if the user has selected a user and if the user chooses with whom he will perepisovatsya, the address bar will be here, this to make two templates, I think it's GKOD, and that you will think so too. Thanks in advance for the help!
April 4th 20 at 01:00
1 answer
April 4th 20 at 01:02
You can start with this:
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