Help With Excel 2011 For Mac High Sierra

I am running Excel 2011 on Mac laptop with OS High SIerra latest version. When I scroll down there are too many rows which I can't delete and the scrolling from my trackpad moves too fast . When I try the recommended "click the row beneath my last entry, shift and ctrl hold down,arrow down to the last row it doesn't work. When I manually scroll down and select all rows below the last entry the rows are deleted when I hit delete and then are immediately replaced with the same infinite number of rows.