If the engine has a port with a dip stick for engine oil then it will be a four stroke engine and will not need anything added to the fuel.
If the engine does not have an oil-filler port then it's a two stroke engine and you will need to mix engine oil (two stroke oil) with the fuel you add.
Examine your engine - look for the oil filler port - I suspect that there will be one.
Good Luck..., April 2017