I have a password in my code which is needed to connect to a sftp server. Whats the best way to "obfuscate" or hide it in the code?
Don't store you password in your source code, store it in a protected section within you App.Config (or Web.Config).
See Encrypting Configuration File Sections Using Protected Configuration section in this Microsoft Doc
This works by encrypting the encryption keys using built-in Windows stuff, locked to the Mac address and various other undocumented things.
This will even work if you are using more than one server:
... if you are planning to use the same encrypted configuration file on multiple servers, such as a Web farm, only the RsaProtectedConfigurationProvider enables you to export the encryption keys used to encrypt the data and import them on another server.
Using this, if someone wanted to get your password, they would have to first break the Windows security on your server (not impossible, but harder than looking into your IL for the password by far).