Travelling Netherlands and Belgium on a budget -- need trip feedback [closed]

If Amsterdam has any place to sleep for €30 per night, grab it as soon as you sure you will travel there at the time.
But do read the reviews as the cheapest places are often cheap because they are very dirty and unsafe.

60€ is more likely and that only on early booking. I have no experience with Airbnb for Amsterdam, for all places I have checked their offers they came close to hotel prices, not hostels anymore.
Amsterdam is one expensive city, I always end up spending more than I intent and so I hear from others. Double what you expect for food and entertainment, I'd say. And that is without doing expensive things like drinking all night.

While there are buses between Amsterdam and Rotterdam, nobody uses them for the whole distance. Train is so much better and hardly more expensive.
The buses are mostly for local transport for the people who live between the cities.
Train is just over €15 if you buy online, or if you have a chip card with at least €20 on it. Which might not be a bad idea, you are likely to use trams or buses in Rotterdam, for which you can use that money.
Rotterdam is slightly less expensive than Amsterdam, might have a bit more in cheap accommodation, but again, book early.

Train to Belgium, is easiest, €34,20 for an adult, there might be a youth reduction I did not find. Coach might be cheaper.
Go for Gent Dampoort, if you have the option, that station is closer to the center of the town.
Again a bit cheaper than Amsterdam, specially a few beers will set you back less, but again not a cheap option.
Not sure about accommodation, I just booked hotels and B&B's and had plenty of choice. But I was not in August, which is main season.

Bruges is even more touristy, worth it, but likely more expensive.

I have no experience with Brussel, but it is not known to be cheap, think prices near Amsterdam again.

As I read somewhere on internet, "Your budget will get you there but without money to enjoy it". Not worth it in my view.

I am a regular (if only for the day) visitor in both Amsterdam and Rotterdam and have been in both Bruges and Ghent for a few days, twice each, in the last 4 years.

In the whole area you will get by with just English, although in Brussels it will be appreciated if you speak French. German is not much of a help anyhow, non of the areas you mention prefers German over English if you do not speak the local language, which is Dutch for most of your trip.

Look for places to eat just before you think about dinner. All places you mention have plenty of restaurants, often also in the cheaper ranges. You may want to look at the smaller side streets for the cheaper ones, which will be needed as your budget is low.

Or get a place to sleep where you can cook and use cheap (super)market food, which makes you miss a whole facet of the countries.

The International Youth Hostel Association provides accommodation with meals provided and /or a kitchen where you can prepare your own food. Also a great opportunity of getting to know other guests. Book as soon as possible.

Bruges is picturesque but not exactly alive and popping.