deleted virtual machine but on boot it is asking for a windows boot disk

Maybe someone can help me here. I went through the steps to remove the virtual machine and partition using the boot camp assistant. The hard drive space is not there any more and the parallels wants me to set up a new partition and virtual machine. When I boot the computer it used to automatically boot windows (unless I held down the option key) ... so now when I turn on my imac it goes to a black screen like when it was booting windows and then says:

the boot disk is not found, please any key to continue.

I then have to power off the computer.

Is there something I can go on OSX to click off the boot priority? or delete this command?

I had to get rid of windows because it was a pain in the ass. It's still a pain in the ass. Even when deleted!

Any suggestions are appreciated!