Struggling to understand my son sometimes 😅

So since my son has started preschool, his talking sooooo much more, his almost 4 years old and could talk my ear off. But his also coming out with new things, like it started off with finishing each sentence with "you understand okaaayyy?", then it just went down to "okayyy?" now he finishes with something I don't understand, he pronounces it as "you-nay-be", he says it everytime his finished a sentence, and says it multiple times, then "okaaayy??". I asked him to say it again but slower, still couldn't get it, then asked him if he can explain what "younaybe" is, he said "you have to ask for my name", so I asked his name and he said "spiderman" (idk, he seems to really believe his spiderman, I've had many conversations with him about it and he won't accept anything else, thankfully he has settled for spiderman ______ and his name), so I ask again, so what's "younaybe?" he goes "spiderman". I'm so confused 😕 if it was "your name be?" as a question, why finish each sentence with it, like "I need potty, younaybe, okayyy?" or even "look, I'm going as fast as sonic! Younaybe" 🤷🏼‍♀️