If you want to check a get the hash for a file (for checking your downloads or generating the hash), you can use the following Powershell command
Get-FileHash .\yourfile.exe
In this example the default SHA256 algorithm is used against some file named yourfile.exe (in this example).
You can change the algorithm use by supply the -Algorithm switch with any of the following values SHA1, SHA256, SHA384, SHA512, MACTrippleDES, MD5 and RIPEMD160.