How to properly set up sql server accounts?

Question

SQL

Hello.
In the logs of the sql server, it always writes this error:

Error: 18456, Severity: 14, State: 5.
Login failed for user 'Domain\PC$'. Reason: No login was found that matched the given name. [CUSTOMER: ]

Domain\PC$ is the name of the computer on which the sql server is running.
Installed sql with all default values, then created a service plan that has a "Manage connection" button. If you create a connection the same as created by default, there will be an error "Failed to connect to the server"
.
I've read a lot and haven't found anything like it. Namely, why by default sql performs its tasks on behalf of the computer account, and does not let this account itself. And you can't create a computer login.
If you add a domain user login and connect on its behalf, the same error will appear in the logs, indicating the computer user.

Authentication costs mixed