I have SQL Server Management Studio 18 - Where I can find SQLServerManager / SQL Server Configuration Manager
To configure SQL client aliases, there is no need for SQL Server Configuration Manager. The aliases are often for client-side usage, so installing the Configuration Manager would be extra hoop to jump through. There are two executables called cliconfg.exe in c:\windows\syswow64 and c:\windows\system32. These should be present after installing SQL Server Client tools or, in your case, SSMS.
The system32 version of cliconfg will create aliases for 64 bit applications, whilst syswow64 does the same for 32 bit. It is a good practice to create aliases for both environments, even if one uses mainly x64. If 32-bit aliases are omitted, legacy applications cannot connect to the database via alias.
For scripted solutions, one can edit registry keys directly. The keys are in paths
HKLM\Software\Microsoft\MSSQLServer\Client
HKLM\Software\Wow6432Node\Microsoft\MSSQLServer\Client

There are several pages how to configure aliases (search for network utility on the latter link). Googling for sql server client alias provides a lot of hits about the subject too.