Students perspective here:
Grades
Germany and Austria are countries where bad grades are possible and commonly accepted. Getting a C or D is what > 50% of the students usually get in the hard subjects. Other countries (e.g. UK) have more of an "if you pass, you pass with at least a B" approach. This can be devastating for new students.
- So check back with your peers and see what grades they really got. If everyone got an A or B, then you need to apply the other answers.
Different country
Even a different university can be a hard change. Most of your peers will have received their bachelors degree from the same university, maybe even a bachelors program that is the logical precursor of your master's program.
They will have learned a lot of specific things that may be needed for the master's program. The professors might even assume that they have learned these concepts.
- They might have more courses with focus on X, while your university focused on Y.
- Their courses might allocate 3 ECTS, but are more like 6 ECTS courses, something that very commonly happens in STEM studies. If your university respected time constraints, you will be at a disadvantage.
Graduate school is meant to be that hard
In my experience, if you are not especially gifted and determined / efficient then yes, graduate school IS hard. I have to work a lot, my peers have to work a lot. There are some exceptions, but these are really outstanding students who have a very special relationship with math and logical thinking. Expect to work 60 hours a week to get done in time. Or get more efficient, which is even harder in the beginning.
Does it get better
No and yes. You get used to it, but my struggle is constant. In your case, I assume that it will get better. Change of location, change of program, change of people... All this will become the new normal, and you will do just fine.
Any advice to survive graduate school?
- Get organized
- Set up a plan, use a calendar to allocate time for learning, and stick to that calendar.
- Set up a list of things to do in the morning, and try to do these things. Make small, attainable goals for these lists (like: solve equation X, read paper Y, write short summary on theorem B).
- Find friends and study partners
- Learning is hard, a group that suffers with you makes it so much more enjoyable. Try to find a group of people that likes to learn on campus / in a cafe that is a little over your current skillset. Expect to prove yourself in form of contributions (e.g. solve homework tasks, explain concepts). Especially in the beginning, try to prepare something others might not have solved yet, or show attempts and reasoning of your solutions. This will make you accepted as a valuable member and your progress will be much faster.
- This is hard during Corona times, but maybe use the class chat to propose a common Facebook / Slack / Mattermost / collaboration tool of your choice to communicate outside of class about problems. Best case is that people will join and ask for help, you help them and learn. Show initiative, it will be recognized.
- Find out about existing online forums for this course. Most of the time there are some kinds of Wikis and Forums that already exist.
- Communicate with your professors about hard problems. In class, ask questions. Out of class, write mails. Attach your attempts and reasoning, much like when asking a question on Stackoverflow. You will learn a lot while doing it, often solving a problem in the process (because, who wants to ask a bad question :P).
- Make yourself known. If they know you they, will care. They will have a face to the name, and they will know that you are trying hard. This requires a lot of effort, because you don't want to be the person that asks dumb questions. You want to be the person that may ask dumb questions but always shows good, constructive effort on solving it first.
- Don't worry. If you pass, you pass. Try to climb the bell curve of grade distribution, but keep in mind that you are in a hard program and this will be acknowledged by future employers and professors.
- You are not alone. There are other students that struggle. Find them, and vent with them. Don't let them drag you down to "we can't do anything about it anyways, so why try", but sometimes a good rant about how hard and unfair everything is, is just what one needs (Do such things in person, no one wants leaked chat protocols ;-))
- Follow the advice of the other comments about finding the culprits of your current struggles.
I somewhat like this book here (free).
It's not for everyone, but I think it can give some guidance. Don't let yourself be stopped by the PhD in the title, almost everything is applicable for your master's and master's thesis too.
It's very controlling, and maybe sometimes unrealistic but it gave me some guidance when I needed to get out of a big hole I dug for myself.