I'm unclear on how to use a virtual piano on my mac, and could use some help!

Hello there, r/piano!

I'm having some issues on how to use a virtual piano on my mac. I have been noticing the sustain on my piano (Korg SP-170) is terrible, and after asking this amazing subreddit how to fix it, it was recommended I purchase virtual piano software. I've decided to purchase Ivory II, but before going through with it, I'd like to clear up some questions I have about how to use it.

First of all, I keep hearing that I have to download drivers called ASIO4ALL in order to not experience huge amounts of delay between playing a note and hearing the note. However, these drivers don't seem to be mac compatible. And after some research, I'm reading that they're not required on macs due to something called "CoreAudio"? However, I'm hearing a lot of different opinions on this matter. Can anybody confirm either way?

Another question is about the MIDI to USB adapters. My Korg SP-170 only has a MIDI out, and no MIDI in. That doesn't matter at all, right? I didn't think so, but I just want to be 100% sure I can use this adapter to connect my digital piano to my computer. I'm guessing the MIDI in is if I want the audio to still output from my piano?

Any other advice you could give me on how to use a virtual piano with a digital keyboard would be greatly appreciated! I think I have it down, but I'm hesitant to make such a large purchase with any doubts in my mind as to whether or not it will work.

Thank you, and sorry for such basic questions! I read the FAQ, but it was a bit too general to answer my questions.