No luck on the old tutorial but see if this helps. There are a number of approaches and I expect someone else will be along with another one.
Draw a profile and path for Follow Me to make the volume of space for flute “cutter”.
Draw the column. In this case I’ve drawing a sector of the column starting with a circle and some radii.
After deleting the rest of the circle, pull it up with Push/Pull.
Intersect the “cutter” shape with the sector of the column and then delete the unneeded faces.
Copy/Rotate the column sector to make a radial array. In this case it was rotate 30°, Enter, x11, Enter to make the required number of copies. The exact angle for the sector and the number will be determined by the number of flutes you want. My column has 12 flutes.
Finally erase the edges on the top and bottom and soften the rest of the edges.