I have a small unpruned grapevine in my suburban garden in Ireland. I am about to prune it now but all of last year's canes start from a point some distance away from the main trunk _ they sprout from older wood,not from the trunk. Should I remove most of this older wood and in doing so lose last year's growth and just leave one one or two of last year's canes (which come out of old arms a bit away from the trunk? I would like to cane prune and not use the cordon method as I do not have room at each side for long cordons to develop.
Outside United States
Below is a link to basic pruning but since you don't want to use a cordon method you could try a modified "tree form with only keeping a 1-2 buds on 4-8 branches radiating out from the central trunk. Just note that you may have more disease pressures due to denser foliage. You may also need to provide some sort of support structure to keep the new growth and grapes from leaning one way or the other too.
Here is the link: https://articles.extension.org/pages/31140/pruning-grape-vines:-an-overview