eng grama question

Both of them are correct.

However, I prefer you to use A.
Usually when we talk about wishes or something that you hope will happen in the future, we usually use were rather than was. It is just the same as conditional sentence type 2.

Example of conditional sentence type 2:
If I were you, I would do the same.

Based on traditional grammar rules, you have to use (A): I wish I were... because what you are going to say is "contrary to fact", and so the sentence has to be in the subjunctive mood. The verb "wish" requires the verb that follows to be in the past tense. Combining the two rules, you have to express the verb "to be" in past subjunctive, which takes the form "were."

I wish I were here yesterday.
I wish he were here yesterday.
I wish you were here yesterday.

However, the use of subjunctive is not very strict in English, and so sometimes you will also see the usage "I wish I was..."

2個一樣
不過i wish i were 就formal d
d人通常會用were...
好似if i were you, i would........

was 都得...不過冇咁formal