MacMini i5 intel possible?

Hello,

Is it possible to get Start9OS to work on a MacMini with a I5 processor?

Almost certainly. Have you had a look at the DIY Community Support section?

Yes. I have tried to install it on my raspberry pi 5 8g but the img I downloaded from GitHub will not booting unfortunately

A Mac Mini i5 and a Raspberry Pi 5 are two different devices entirely.
v0.3.5.1 does not work on a Pi 5. - v0.3.6 will.

I know that. I wrote I have a MacMini and raspberry . I can’t get it work on the raspberry pi 5 from the GitHub image