There is not enough info to ask that question. There are many different models of craftsman mower. Please ask again and include the model of the mower, the engine make and size.
30 wt
what grade of oil on this engine
Depending on the model of the Craftsman lawnmower, there is either an oil plug underneath the deck of the mower which needs removed to drain the oil or the lawnmower needs tipped on it's side to allow the oil to drain out through the oil cap area. Once oil has drained you will want to refill the oil until the dipstick registers "full".
Your owner's manual should explain that.
5w30
Click the link and then look up your engine based on the model number.
30 weight oil can use car oil or lawnmower oil same oil
youtube - push mower oil change.... oil plug under mower deck
Sae 30w
A manual for the Craftsman lawnmower model 944.607853 can be ordered from the Craftsman company. Another option is to contact the store where the lawnmower was purchased and have them order a manual.
If its a push lawn mower. It has no oil release. The mower burns the oil. All you do is replace the oil when it gets low.
SAE 10w30 full synthetic any major brand.