Basic but maybe dumb question is there an autosplitter for this game i'm new to speedrunning but I love castle crashers and want to speedrun it but i'm not sure of my ability to split correctly.

No autosplitter exists for this game as of now. Splits are there to check how your run is going as well, the only splits that really matter are the first one and the last one, but the mod that verifies your run should double check them as well.