Cakes are burning

i put the cake on 180 as it says on the recipe but then my oven is a fan one would this be why the cakes burn on the outside and the inside is taking longer

It's time vs temp. That sounds like the temp is too high or not evenly distributed in the oven, so it needs more time and less heat. Put a cooking thermometer in the oven to make sure it is in fact, 180 degrees. Be sure the thermometer is intended for cooking.

Yep. I would suggest reducing the temp, and cooking for a longer time. That's generally the first thing you try when something doesn't cook evenly.