Zend certified PHP/Magento developer

Digital Signature for project

i want to know for me to sign digitally software(i am not a developer just an investor)

Do i need to use services like comodo or it can be done manually, for example i freelance soft like desktop app for speed up pc. Now i need to sign it with EV certificate right?

I do need this for:

  1. Windows Defender acting normally with my soft
  2. Browsers does not notifying about suspicious website

Am i correct or it is not true?

And if i need it, can i do it manually some how or need to do via comodo like services?