I have got as far as you have given about pruning grapevines but you did not, it appears, show how to prune them.
Main rod and secondary rods are permanent.
From the secondary rods each year grow the flowering/fruiting stems. These are stopped at one or two leaves past the flower. All other unwanted shoots are taken off every two weeks when small. The fruiting rods are pruned in winter back close to the secondary rods.
The photo with fruit shows the fruiting shoot. https://gardenie.wpengine.com/gerrycategory/grapes/?id=5437