They are both correct. " It will be received in 2018" is known in English as a "passive" statement and "I will receive it in 2018" is called a "direct" statement. In all of my college essays, I was asked to use direct statements. So for a paper I would say, "I will receive it in 2018."

I wouldn't see anything wrong with saying "I will receive it in 2018" but either could work.

There's nothing inherently informal about using "I", but sometimes you want to be impersonal -- scientific articles are the classic case -- and so using a passive construction achieves this. It puts the emphasis on the target of the action (the degree, here) rather than the agent. But if you are going to do that, note that using "received" as the verb redirects the emphasis back to you as the recipient. So, if you are going to use the passive -- and again, I think the active here is fine for most purposes -- better to say "granted" instead, because it is about the degree.

No problem with it.you don't give your personal opinion.

Future tense : I will receive my Bachelor's degree from ( name school here ) in 2018. Past tense : I received my Bachelor's degree from ( insert school name here ) in 2018.