Swiss alpes from Milan

I see that you are flying in and out of Zurich for this 14 day trip. You have a lot of places on your itinerary and you seem to be going in all kinds of directions. You will waste at least a 1/2 day if not more each time you fly in and out of a city. (or train/bus to and from major cities). I would suggest you eliminate some places from your list. Day 1 - I am puzzled by your plan to go to Lauterbrunnen for just one day to return to Zurich that night - only to return to the "Swiss Alps" at the end of your trip. Lauterbrunnen and the surrounding area is worth 4-5 days. Arrive in Zurich and head directly to Lauterbrunnen in the Swiss Alps.. Stay for awhile. I would choose to either go towards France and make my way to Paris (if that is a priority for you) or go south to Milan (by train) and then onto Venice and Rome. You could fly from Rome to Zurich. You really don't have enough days to include all the places on your list. Eliminate Amsterdam and Munich and pick France or Italy. I think you need to re-think your whole schedule.

You realize that the Sunday May 14 10 pm bus to Munich will leave you at the Munich bus station at 3:15 am.
If you have not already booked your internal flights, stop and rethink your itinerary. You can get a Thalys train from Amsterdam to Paris in 3 hours and 18 minutes, less time than flying when you consider traveling from central city to airports both ways, time waiting to check in, security, boarding, flight time, deboarding, waiting for luggage.
My rethink:
Skip Munich, instead, take a train to Paris, its only 4 1/4 hour. 3 nights, then take the Thalys train to Amsterdam for 3 nights, then fly to Rome, 3 nights there, then train to Venice 2 nights, then train to Lauterbrunnen, 2 nights, train to Luzern, 1 night, morning train to Zurich airport for flight home. Even this would be a bit hectic for me, but it hits all your spots (except Munich) with enough time to spend one or two full days at each spot.
PS. Your original question, www.sbb.ch/en to see the trains from Milan to anywhere in Switzerland and on to Zurich.

don't miss a key point: Lauterbrunnen (of which you only plan to have a couple of hours to enjoy) IS in the Swiss Alps. You seem to be going a long way out of the way at the beginning of your trip, only to double back again later.

You should also realize that hopping around Europe like this, you will spend much of your time (I am estimating about 6 days worth) in traveling between locations. Much of your holiday will be spent on trains, planes, airports and rail stations. Not saving time by flying between cities, since you have to get to and from airports, checking in and security, etc.

Thanks everyone for all the answers :)

Germany is a must go for me. I really want to see the castles and the concentration camp in Munich. in my mind, I thought two days would be enough there. even though, I know I'm going to be exhausted on the first day there. The reason for going all the way up to Amsterdam is because my best friend wants to go there (is her must place) I don't know why. So, I need to go with her as she is going to Munich with me.
This trip is my first trip to Europe, I think I got very excited trying to go everywhere lol. I even wanted to add London from paris and Monaco hahaha (cray-cray) maybe because I'm Brazilian and we think that everything is possible lol.
Another question, do I need to buy the train tickets to Lauterbrunnen now or can I buy when I get there?
also, from Paris to go to Italy (Pisa, Rome, Venice, and Milan for few hours before we get the train back to Switzerland ) what would be the best route? I'm sorry, I don't know if i'm making sense putting all this together in English. But I do appreciate all the help. :)

Another question, do I need to buy the train tickets to Lauterbrunnen now or can I buy when I get there?

To Lauterbrunnen from where? Assuming you are keeping to your original plan, that would be from Zürich Flughafen (airport) station. As this is an internal Swiss journey, there is no discount for advance purchase, the same price applies throughout the day and no reservations, tickets are valid on any train. Just buy it on the day at Zürich Flughafen station.
It will cost CHF 83 (2nd class per person, each way) and take about 2½ hours. For times see: http://www.sbb.ch/en/home.html

Paris to Pisa or Rome is too far for a day train, you should fly that leg.
Except, as Stan points out, your plan has you visiting the Swiss Alps twice, at the beginning and end of your trip. This is illogical.

I suggest you print out a map from the internet, mark the places you want to go, and try and join them all up with the shortest possible lines. Why are you flying into and out of Zürich? Why not fly "open jaw" (into one city and out of another). That would save doubling back.
For example: Fly to Amsterdam (train) Paris (fly) Munich (train) Swiss Alps (train) Pisa (train) Rome fly home from Rome.
That is 6 places in 14 nights. I would still say that is too many. You may have to be ruthless and cut 1-2 out - sorry!