OpenCore will ask you to relaunch as root. Select yes.

Then OpenCore will start patching your MacOS installation to make it compatible with your Mac.

After it finish to patch, it will ask you to reboot apply patches.

Be sure you still have the second USB you created plugged in, or you won't be able to start your pc yet.

While your Mac reboots, hold down the [option] key to enter again boot disk selection. From there, select again EFI Boot and your Mac will start normally.