Measure two qubits, one from entangled pair, in Bell basis?
I figured out that as we are operating on 3 qubits ($|v\rangle$ and $\beta_{00}\rangle$ pair) and we want to perform CNOT on the first two (if we enumerate like 1- $|v\rangle$, 2- first from pair, 3 - second from pair) it is just like we want to perform $CNOT \otimes I$ on $|v\rangle \otimes |\beta_{00}\rangle$.

After performing the CNOT described above we need to perform H on the $|v\rangle$ qubit, which is now entangled (as CNOT is an entangling operation), so it is like we want to perform $H \otimes I$ on the three (where $I$ is 3 x 3 identity matrix).

Beaing able to perform both steps described above we are able to perform a measurement of qubit $|v\rangle$ and the first qubit from the entangled pair $|\beta_{00}\rangle$ in the Bell basis.