@Nuran Please don't post URL to other external website, other help desk platform or seems your profile is mading spam.
I edited the URL in your message.

But I need only member panel as main page

I don't know how to help. UVdesk load the basic Knowledge page when you load the main address.
You want redirect this to the customer login page? Maybe in this case you can see if you can manage your hosting to do a redirect but should be ok simply use UVdesk as is. Seems you are asking a customization so I cannot help with that. Maybe you can try to wait a UVdesk team reply but again, seems you are asking for a customization...

If you run an help desk system is normal that the main page will be the main page of the Help desk system.

If when you load yourhelpdeskdomain.ext want load yourhelpdeskdomain.ext/member/login you need put a redirect on your hosting.

On Apache you should be able to do this with a redirect. you can search how on Google.
"redirect with htaccess" or some panel do allow do this by using the web interface.