CentOS

Good afternoon.
I have Centos 8 Minimal installed on a hyper-v virtual machine. I get errors below. Help me please. What should I do?

12:29 Buffer I/O error on dev sr0, logical block 1, async page read kernel
12:29 Buffer I/O error on dev sr0, logical block 0, async page read kernel
12:29 print_req_error: I/O error, dev sr0, sector 0 flags 0 kernel
12:29 Buffer I/O error on dev sr0, logical block 7, async page read kernel
12:29 print_req_error: I/O error, dev sr0, sector 7 flags 0 kernel
12:29 Buffer I/O error on dev sr0, logical block 6, async page read kernel
12:29 print_req_error: I/O error, dev sr0, sector 6 flags 0 kernel
12:29 Buffer I/O error on dev sr0, logical block 5, async page read kernel
12:29 print_req_error: I/O error, dev sr0, sector 5 flags 0 kernel
12:29 Buffer I/O error on dev sr0, logical block 4, async page read kernel
12:29 print_req_error: I/O error, dev sr0, sector 4 flags 0 kernel
12:29 Buffer I/O error on dev sr0, logical block 3, async page read kernel
12:29 print_req_error: I/O error, dev sr0, sector 3 flags 0 kernel
12:29 Buffer I/O error on dev sr0, logical block 2, async page read kernel
12:29 print_req_error: I/O error, dev sr0, sector 2 flags 0 kernel
12:29 Buffer I/O error on dev sr0, logical block 1, async page read kernel
12:29 print_req_error: I/O error, dev sr0, sector 1 flags 0 kernel
12:29 Buffer I/O error on dev sr0, logical block 0, async page read kernel
12:29 print_req_error: I/O error, dev sr0, sector 0 flags 0 kernel

It's telling you that it's unable to read whatever is in the "CD/DVD" drive on that VM. You should verify if the iso image or physical device that is attached to it is functioning correctly.

But I don’t have anything in the “CD / DVD”. I have now deleted the "CD / DVD" from the virtual machine. Errors have stopped yet

Well /dev/sr0 is your virtual optical drive inside the VM. It's trying to access it and getting errors so it presumably thinks there is media in it and that it's corrupt.