The statistic t for linear regression with robust standard error

I need to calculate the statistic t (without any softwares or this sort of things) for a linear regression with the robust standard errors already computed. I know that in order to get the t statistic I need to do

t = b1/standard error

Where b1 is the slope coefficient. However, I trying to understand two things (1) how does the robust standard error is used to calculate the statistic t? (2) how does that change the comprehension of the statistic t?

I just couldn figure that out.