How do you associate a host and an SSH key when you connect to a .com VPS from Windows?

"If you search ""SSH Permission denied (publickey)"", there are many solutions, which may be because there are many causes."In my case,

• Local OS: Windows 10
• VPS OS: Ubuntu 20.04
• Provider: Name.com
• Services:VPS (KVM)

The provider factor is very important.If your name is com,

It is easy to connect with TeraTerm, but sometimes it is necessary to connect without using TeraTerm.
When I heard the question, I wasn't familiar with SSH, but logically, the meaning of SSH Permission denied (publickey) is "I don't know where to get the key to connect to the host 15X.X.XX.X:10022.If so, how should I remind you?

The downloaded key is in the CC:\Users\User_Name.ssh 」 directory.The file extension is .pem.You should be able to specify a filename.

PS

It was not successful to be referred to com support.