Problems installing Mojave to 2017 iMac.

I am having a problem installing OS Mojave to my 2017 iMac. I have a 1 TB hard drive and am currently running OS High Sierra. I have looked at the error log and it is stating that I have a SATA hard drive and I need an APFS hard drive. At this point in time, I have also lost the ability to look up the information about my iMac from the Apple symbol. I was able to download Mojave but could not install. When I went to install and it asked me to pick my hard drive, the hard drive was grayed out and I could go no farther.

Thanks!

Lois