This ignores millennia of Christian thought that addresses exactly these problems. You think we're unaware of these questions? It's honestly insulting.

In brief,

1. Genesis is poetry, not scientific literature, inconsistency is often intentional and for a particular literary purpose (read Through New Eyes for details, chiasms often play a part). Old vs young earth is a valid debate, but both are consistent with the Biblical narrative because it features a transcendent God who is not bound by the laws of nature.

2. Science is often wrong (at best it's a method of inquiry, not a set of doctrines). Estimates about the age of the earth depend on the doctrine of uniformitarianism which Genesis explicitly denies. Likewise, the doctrine of evolution is just that, a doctrine.