Certified GKH Gardening Expert
You can prune, but it is a personal choice as to whether you do it. This article will explain more: https://www.gardeningknowhow.com/edible/vegetables/tomato/should-you-prune-tomato-plants.htm
They do not need pruning. Keep them off the ground by simply supporting them with tomato stands (should have been put on when planted), or you can use a 4' tall roll of large diameter chicken wire from Home Depot, making a ring around the plant, if you have no other support in place.
You may need to hammer stakes into the ground up against and tied to the support cage to keep it from falling over from it's own weight. The plants get large and somewhat heavy, especially while they establish fruit. Use planting ties to tie the branches to the cage. Then get ready to start canning tomato sauce! Roma's are the primary tomatoes used in sauces for their great flavor!