In FreeBSD, switching between consoles is with the Alt+F1 combinations. If X is running, Ctrl-Alt-F1 must be used to switch to the text console. Then the Alt+F1 combinations work. To switch back to X, it is usually Alt-F9. However some setups might have X at a lower-numbered function key.
Note that FreeBSD is just one of several BSD-based operating systems. NetBSD and OpenBSD might do consoles differently. There are also appliance variations that use FreeBSD that also might do things differently, like FreeNAS, pfSense, and opnSense.