Calculating Standard Error from Linest

I graphed some data as a bar chart and included positive & negative standard error bars. When I try to have the calculation of standard error in the associated data table, I find that the only function available is the standard deviation, which is related but not the same. My understanding is that the Linest function will produce an array of numbers, one of which is standard error, but I cannot figure out how that function works. How is the array produced? I tried inserting the Linest function in a cell of a table separate of my data table but it only put the number which is in the A-1 cell of the array shown in the Linest explanation and I don't understand how the rest of the array is filled out. The standard error for Y, which is what I am trying to obtain, is in cell B-4 of the array as I recall.