Why do you keep saying 'Germany and Amsterdam' as if these are equivalent destinations? Germany is a big country with varied regions and landscapes and varied cultures within those regions. Which bit of Germany do you have in mind?
Germany and Amsterdam, because I've always wanted to visit there. I don't even know why. Just wanted to. If I have to clarify some places I have heard of and would possibly like to see is Anne Frank house, Van Gogh Museum and in Germany Lubeck and Berlin
And what time of year wil you travel? This can affect what there is to see and how busy the trains are.
I planned to start next month.
You can certainly travel through 8 to 10 countries in the space of a month, but why? Do the maths -- in 30 days, take out 8 to 10 days for travel. What can you do with the remaining 20 days?
I thought something of 10 countries 20 cities or something like that. I've heard people do that much. This also sounds what I'd like to do -- See as much as possible in a month period of time, but not too much. I don't really want to sit down, I just want to travel and see the world.
Also, with the Interrail ticket you are buying a certain number of days of travel. You will need to do some planning to decide where you will want to end up at the end of each day.
And maybe you don't need a pass. Maybe point-to-point tickets by train or bus will serve you better. Read about Interrail here:
https://www.seat61.com/InterRail-pass-guide.htm
I'm familiar with the thing people saying you really don't need a interrail card in some occasions. I was thinking about Global Pass -card. With this you can travel a month period time as much as you want. It costs around 500 euros. I personally feel interrail card is more safer and easier option to go with. It doesn't really cost that much.
To give you something to consider as a first-time visitor, a route with a focus on Germany and Eastern Europe that hits some of the classic spots and all with daytime travel to enjoy the views: Hamburg-Berlin-Dresden-Prague-Vienna-Budapest-Ljubljana-Zagreb. Fly home. Or from Budapest travel to Belgrade, and then fly home.
These are mainly the tips I'm looking for. Thank you. (But you left out my dear Amsterdam!)
I'm thinking about 10 countries 20 cities. How "true" or realistic this sounds to you in a month period of time. I know in the end I choose the route and all, but I'd like to just get some contrast on this -- other people wants to chill on their interrail trip -- I want to live as cheap as possible and see as much as possible, but not too much. I don't want to end my trip in a hurry.
I understand this can be difficult for you to answer, since you don't know my true (hell, even I don't) view on the thing, but I'd appreciate your help and tips.
E: I'd like to do as little planning as possible what comes to the places I visit. I am spontaneous and I'm really not a nitpick type of a guy. Of course I'll do tentative planning to what countries I'll visit -- but other things might come with an element of a suprise. I'm sure you know what I mean and how I think through this. I'm also thinking this might be a little naive point of view for this, but... I'll live with it. I guess.