Assuming it's a four cycle engine, just regular motor oil should be fine. The weight kind of depends on the temperatures you will usually operate it in, but 10w-30 is a pretty good compromise across the board. I use the same oil (Castrol 10w-30) in my mowers and all my cars. Temperatures here can range from extreme cold down to zero in winter to extreme hot maybe 110 in summer. Normal is more like 25 to 100.
You can probably find an operating manual online, if you want to check just to be sure.
Aries
~Sign of the Rams
Aries
~Sign of the Rams