How to Install .Run Files on Linux

I'm new to using linux and I wanted to install Metasploit.

I used the chmod command to make it an executable file and then tried using the sudo command but is returns an error saying that the command is not found.

Here is the error:

paul@freedom Download$ chmod +x metasploit-latest-linux-x64-installer.run

paul@freedom Download$ sudo metasploit-latest-linux-x64-installer.run

sudo: metasploit-latest-linux-x64-installer.run: command not found

paul@freedom Download$

Please help!

Thanks!