What are the things your service dog is trained to do? I don't have nor need a service dog, but I'm curious to hear what people's service dogs do to help them because each service dog is different and trained to do different things.
The short answer is that service dogs are trained to do the things that the person cannot do for themself.
All service dogs are trained at an advanced level in obedience work, are extensively socialized, and then later are matched with a person. When they are matched, the trainer will find out what the person is needing and can train the dog these extra skills. They also match you based on things like your lifestyle, how active you are, and what your home environment is like.
I was just starting college when we started looking into service dogs. We were looking for breeds that had good stamina throughout the day but were not hyperactive. Since most of the dogs that are trained to be service dogs are labs, Golden retrievers, or german Shepard's, we had to look a long time. We looked into a variety of working breeds and completely by accident found a young St. Bernard that had everything a potential service dogs needs. A calm temperament, being friendly but not excitable, liked to be out and meet new people but was also ok with having a stay home day, and was smart and motivated enough to complete all of the training classes and tests.
My specific scenario was I had a spinal cord injury which lead to multiple spinal surgeries. After a few months I developed muscle atrophy and developed severe scoliosis since I was not able to hold my torso straight. I had multiple surgeries to correct the scoliosis where they put an extensive system of rods and screws to try and stabilize and straighten my torso. After we were done with this, I was extremly inflexible and was not able to bend over or twist at all.
So we worked with my dog to teach her to do anything related to low down reaching, reaching out in front, or moving heavy objects.
Basic retrieving skills were helpful for dropped keys or a dropped phone. Then we started getting more creative and taught her how to grab laundry out of a front loading washing machine and bring it to me so I could put it in the dryer. We also taught her how to get boxes and packages of food out of our lower cabinets, bring me Tupperware, pick up dropped utensils in the kitchen, and open the fridge door for me and close it. She also helped me unload the car after a trip to the grocery store by carrying in the grocery bags, or help me bring in my bag and keys.
Another issue I had was with muscle atrophy. Since my spinal cord injury was a few inches above my belly button I lost a lot of muscle in my lower abdomin, back, and legs. My balence became extremly unstable and I couldn't bend over and then couldn't reach forward. I had trouble picking up heavy things off the floor, reaching out in front of me, opening heavy doors, and putting on a backpack. Anything that required a bend, reach, or twist was a challenge.
You can teach dogs to do so many creative things based off of a few foundational skills like retrieving or touching. They can learn to push with buttons with their nose in elevators, push open heavy doors with their heads, help you carry things to your classes at school. It is really amazing how helpful they are for people that need them. It is also such a contributor to independence. Before I got my dog, I had to ask my mom or sister to go with me to help with things like opening doors or carrying bags. Having a service dog helps people that are semi-independent become mostly independent in many ways.
Another thing that they do that you don't have to teach them, is draw in positive attention. I have always been very shy and to myself. After my injury I felt like people were hesitation to talk to me because they didn't know what to say. When I got Lily people became very friendly and open which really helped me re-adjust. Everybody is excited to see a dog and so many people come over to say hi. This was just an unknown benefit when I got her. Having a service dog really makes your interactions with the world very positive and friendly. It has been such an incredible learning experience so far.