As per Honda Civic's manual, you replace all filters and lubricants of your car on completion of 40k running.
People sometimes mix the term Fuel Filter and Oil Filter.
Oil is the Engine Oil that should be changed every 5000kms. Best is to change oil filter as well.
Fuel filter is changed every 40,000kms running. This filter comes in a plastic assembly. Your previous oil filter, which is fitted inside fuel tank under rear seats, is taken out, fuel pump is removed from the assembly and fitted in new assembly.
As for synthetic oil, I recommend using only organic oils. Engines survive better on natural products! Better change oil early than to put unknown stresses on engine.
Best way to know about maintenance routine of your Reborn is to read and understand its Manual.