You will first have to decide if you require/want 30 or 50 amp service. Remember that the RV world slang "50 amp" is two 50 amp legs of 120VAC so actually "100 amp service" (arguably). This decision is usually a "need" based decision dictated by something like multiple air conditioning units. Also, deciding to go with "50 amp service" does not mean 30 amp connection cannot be used.
Once that decision is made, I am a big fan of hardwired cord as John previously described. Mine is mounted on a powered reel (
https://amzn.to/34FK5wd) which makes stowing very simple (and that can matter if you've ever attempted to hand roll a long, cold, 50 amp cable.