Think of your puppy as a human baby. He has no skill sets and you will have to patiently educate him to become a good dog citizen.
Never yell at mistakes and accidents. I have always made what I guess you would call a sad face and a low, sad, disappointed sound for these occasions. Since Libby looks at my expression for clues, I consistently make the face and sound to let her know if an action is unacceptable. I use a pleased expression and approving voice to let her know when I am pleased with her behaviors.
Get used to supporting his back when you pick him up. Use two hand to lift him, don't just scoop him up with one hand. If you do this from the start, it will become automatic for you.
When he transitions from puppy food, find an excellent nutrition food to feed him. Dachshunds shouldn't eat a lot, they will want to, but you are in charge of the amount and the nutritional value of what they eat. Supermarket brands may be cheaper, but since dachshunds shouldn't eat a lot, it doesn't cost much more money to feed a quality food. Empty calories in poor quality food can lead to all kinds of problems because your dog is not getting the nutrition he needs to grow and be healthy. Also, do not let him get overweight. This could cause back problems and you do not want that to happen.
I always carry Libby up and down long flights of stairs to prevent back problems.
There is a lot of useful information in this forum. You can use search to find threads that address specific topics. Read, read, read, and just love him.
Don't buy into the dominance myth and all that Cesar Milan garbage. It's not based on science and can really harm your dog. Not saying Cesar doesn't have some things right, but don't try to train your pup using his methods. I followed his show religiously when I got my first dog and way over-corrected her. I know I contributed to her fears of people, because I was so worried about her being "calm and submissive" that I didn't make meeting new people a fun, positive experience.
Your puppy may be completely confident and balanced, but it's best to assume he may be unsure of new things, and always make things positive. Socializing him (which is very important) doesn't just mean exposing him to lots of things and people and animals, it means pairing every new exposure with praise and treats and things he loves.
And along those lines, pay attention to what he loves. Dogs are individuals, just like us. I love reading and potato chips and red wine, but you might hate wine and love movies. Some dogs find petting to be a wonderful thing, while others may be all about chasing a ball or de-stuffing a toy. Let him try all sorts of things (different treats too) and find out what he adores. This will be invaluable in training, because you will find he will do just about anything for the right reward.
House training can take a LONG time! Be patient. Put in the time in the early days and weeks and it will pay off eventually.
Decide how you want your dog to behave as an adult and work towards that from the start. It is much harder to "un teach" things. My younger dog has been sitting and waiting at doors since she was 3 months old and it's just habit for her now.
Take tons of pictures and video! They grow up faster than you realize and you'll want to be able to look back on their puppyhood.
Remember above all that you are totally responsible for his health and happiness. Our puppies didn't choose us, we chose them. So don't deprive him of your love and attention, even when you're tired or feeling frustrated. Let him be a dog and roll in smelly stuff sometimes, and explore his world.
Doxie puppies are the best-so cuddly and loyal. You will have a great time with him!