First, remove any debris from the fence and then use a brush to clean the surface. If the fence is painted, you will need to remove the paint with a remover. You can then use a wire brush to remove any loose or peeling paint. Once the surface is clean, use a wood putty to fill in any holes or cracks in the wood. Let the putty dry completely and then sand it smooth. Paint or stain the fence as needed.

You can repair a wooden fence by using wood glue to adhere two pieces of wood together, then using nails or screws to hold the glued-together pieces in place. Another method is to use dowels to reinforce the damaged area, and then attach new boards using screws or nails. Finally, you can also use a wood sealant to protect the repaired area from moisture and weathering.