OK the thing is my PS2 Phat had broken lens (twice) so I gave up on it which was like years ago and today as I searched the net for any workaround I found that it's possible to play ISOs on external Hard Disk but they say it's not recommended since its slow. Then I didn't know that there's this expansion bay on it and its actually possible to put a HDD and a network adapter is required on it but I'm not really sure how this works. I'm not knowledgeable on this and the info I've found so far is incomplete

Also my PS2 can run burned games, I don't know how but I think my brother went to a shop somewhere to modify it (Is that how mod chip works?)

My questions is:

1. How do I put the games on the HDD?
2. Do I need a special software from computer to transfer ISO?
3. Is the HDD PS2 specific or anything works?
4. Do I need internet connection for this?
5. Any recommendations for the controller? Because I can't find my controller at home, probably broken or lost
6. Will a usb stick as a memory card work for this setup?
7. Do I need a different firmware for this? Or the default one works?