Welcome to RCU. No, 4-strokes are still nitro powered engines too. I would stick to a 2-stroke engine while you are training, they are a little bit easier to tune and maintain than a 4-stroke. And a new pilot has enough to learn as it is, you don't need to be messing with an engine on top of that. A good OS 46 AX would be an outstanding engine for that plane. There are other engines too, but I don't have first hand knowledge with them so I'll leave the recommendations to those that do have first hand knowledge.

Hope this helps

Ken