Side Bar Question

the sidebar is called in your theme. The default side bar function is get_sidebar() just add this where you would like to call it.

control which page gets a sidebar and how to remove the side bar

you could try to wrap the ‘get_sidebar()’ code into a conditional statement, using https://codex.www.ads-software.com/Conditional_Tags

most likely, you will need to adapt the css styles.
you can use page specific css classes output by body_class (at least in your example linked site) to do target the individual pages.

You are very kind to give me advice. I appreciate that. But there is a way through the dashboard I am sure. If anyone knows how to do it through the dashboard it would be appreciated.

you cant add that function through the dashboard. It will have to be added manually.

Sir please tell me not showing the my sidebar but php code in the sidebar is correct please tell where is problem the code is totally rite now but not show the sidebar on my blog

Thanks for anticipation

plzz tell me

Sir please tell me not showing the my sidebar but php code in the sidebar is correct please tell where is problem the code is totally rite now but not show the sidebar on my blog

Thanks for anticipation

plzz tell me