Very sorry to hear brother.
You’ve answered your question. This is a classic case of ■■■■ induced erectile dysfunction. Your brain has become wired to only experience arousal from watching pornography. There is only one cure. Complete abstinence from watching pornography. You have to leave it behind for good.
Do some research into this condition yourself. I highly recommend the book Your Brain on ■■■■. I’ve written a summary of the book here which can get you started.
The bad news is you have really damaged your sexual health through your pornography use. You’ll need to leave your penis alone for the next few months. Depending on the severity of your addiction, that could be 6 months of complete abstinence from pornography, masturbation or sexual activity, however many people recover after 3 months.
The good news is that your sexual health problems are not physical - it’s not broken, and you don’t have some low testosterone issue. You just need to stop watching pornography and masturbating. Even a five second peek will delay your recovery - all of it is toxic for you. Leave it behind completely, and you will see a return to health in 2020.
Best of success to you brother.