Here's what happens, turn oven on, in fan mode


However after a short while the glow goes out. The main fan which also can be seen in that pic at the back is not spinning, but I can spin it freely if with my finger ( when the oven is cold! ) I can hear another fan somewhere , guess that's something else? After a long time the oven heats up a bit, but not to full temperature and seems to get cold again really quickly.
The conventional oven

I'm guessing it might just well need a new fan / motor mechanism (this one I think https://shop.ukwhitegoods.co.uk/mtr295-oven-fan-motor ) but before I order it, I wanted to check in case there could be another problem. Should the element be glowing throughout , has that had it too, or is that happening because the fan is not working? Would it be a plan to order a new element anyway?
Any thoughts and ideas very much appreciated!
Many thanks
Ian