For BER vs SNR analysis of BPSK, I am using Simulink and BERtool in MATLAB. Shown below is the Simulink model:

In AWGN component, the parameters are set as below:

Then I open BERtool -> Monte carlo. Here, Eb/No is selected to be from 0:1:10
It is not changing the Eb/No value in AWGN component for each iteration. What does Eb/No value do exactly in Monte Carlo simulation?