-) basically the New F-1 will work with any flash that works indepentant of the canmera, in manual or in autoexposure mode, as long as it gets the trigger signal (with shortcomings with bulb flashes due to only X-synchronisation available).
-) the New F-1 can comminacate with a resp. flash (early form of dedication)
setting of sync speed as long as flash is charged
transfer of auto-aperture set on flash to the camera finder (but still to be set at the lens!). This even does not work with all finders
No TTL !
The grade of dedication thus is limited.
-) If this dedication is important to you, you can choose from 8 Canon flashes listed in the manual.
These differ in power, number of auto-apertures and moveabilitiy of reflector.
-) Alternatively for this you can choose from dedicated flashes made by other manufacturers
The german manufacturer King Regula made some models that got various contacts at their incorporated hot-foot and a switch for several camera brands, by this switching the right contact and algorithm. Some of these are more advanced than the Canon models.
Also any german flash with a SCA foot added with the adapter 310 or 311. This gives you a huge range of flashes.
Similar with the dedicated Sunpak flashes, and likely Nissin.
