having problems to download iTunes

i'm having trouble to download iTunes on my MacBook Air 2020. my iPhone is disabled and asking me to connect to iTunes, I did try everything it asked me but still I can't download the iTunes.

it would be grateful if I can get to help to sort this please.

my other iPhone was stolen and I think the person stole my phone has my passcode so I'm trying use another iPhone so I can erase the one was stolen. please tell me what I can do to download the iTunes to my MacBook many thanks. by the way I'm in Somalia and there's no help I could get to sort my issue.

the phone I'm asking to get help is iPhone 12 Pro Max and its a brand new one. I put too many times

Kind Regards,

F