The Business and Business + tariffs allow you to work with hosting using the ssh protocol. This protocol allows you to access hosting files using an ssh client.
To enable ssh access for your user, you need to go to the hosting control panel. If you have several sites, you just need to enable ssh on one and it will become available for all sites, since it is actually enabled for the main login.
On the Hosting and DNS tab, select the Hosting section. In the window that opens, enable ssh access by selecting the option from the drop-down list.
Click save and try to connect using the login, password and IP address indicated in the screenshot.
Please note. Enabled ssh access makes your site more vulnerable to password guessing by various bots on the Internet. It is important to use a password consisting not only of letters and numbers, but also using symbols.