If you’re going to invoke the resurrection as evidence for God’s existence, we first need to try to estimate the probability that the resurrection even occurred. The form of the argument seems to be something like the following:
Only if A is the case(God exists) and for no other reason, would we expect B to be the case(the resurrection occurred). B is the case(the resurrection occurred), hence A(God exists) must be the case.
Now obviously you can’t just say that the resurrection is likely to have occurred because God exists. And God is likely to exist, because the resurrection is likely to have occurred. That would be straightforward circular reasoning.
As an atheist I obviously don’t grant the premise that God’s existence is likely. Hence if you want to show me that God exists by appealing to the resurrection, you need to show first that the resurrection even occurred, and that only if God exists is that likely to have occurred.