I’m pretty sure they all mean to see but is the difference just in formality? I’ve seen people say that 뵙다 is the most honorific and 보다 is the least, but I’ve seen those same people say that 뵙다 can also be made informal?? And that this has nothing to do with speech levels??
뵙다/뵈다 are replacements for 보다 and 만나다 "to meet" when the person who is being met is more elevated than the person who is meeting them. So when A meets B, if A < B, then you use 뵙다/뵈다, and if A >= B, then you use 보다 or 만나다. ("A < B" indicates B is more elevated than A in terms of social status.)
뵙다 cannot be conjugated with verb endings starting with -아/어 or -(으). For example, *뵙어서 and *뵙으면 is impossible. In these cases, you have to use 뵈다: 뵈어서 (shortened to 봬서), and 뵈면.
Other than these grammatical differences, the difference in meaning or nuance between 뵙다 and 뵈다 is marginal.
The word "Speech level" is usually used to indicate the level of politeness and formality towards the listener of your speech. 뵙다 and 뵈다 do not; they only show politeness towards the object of the verb, and it is completely independent of the listener's status. In other words, all speech levels are possible to use with 뵙다 and 뵈다:
In polite informal speech level (해요체):
오늘 저는 할머니를 뵈었어요. (저 < 할머니)
오늘 저는 친구를 보았어요. (저 ~= 친구)
In impolite informal speech level (해체):
오늘 나는 할머니를 뵈었어. (나 < 할머니)
오늘 나는 친구를 보았어. (나 ~= 친구)
In polite formal speech level (하십시오체):
오늘 저는 할머니를 뵈었습니다. (저 < 할머니)
오늘 저는 친구를 보았습니다. (저 ~= 친구)