People living off 'social minimum' in the Netherlands have a netto income of 1120 euros.
Any housing with rent below somewhere around 750 euros is considered 'social housing'.
If you live off social minimum, the tax office will grant you subsidies, coming down to you yourself having to pay 300 euros rent, and the state paying the rest. This is only possible if you live in social rental housing (rent below the 750 mark).
Housing in the social rental sector is in very short supply. Living with your parents until 35-40 is no exaggeration, nor a joke nowadays. Expect to have to wait 15-20 years to be egligable for such a home.
So from an income of 1120 euros, you pay 300 euros rent, the state pays the rest. If your income increases, the subsidy decreases.
You pay between 100 and 300 euros for gas and electricity, depending on how much isolation and other sustainability measures have been taken in your home by your rental company.
You also pay somewhere between 140 and 180 euros each month for health insurance. Mandatory. Not having / paying for a health insurance is an offence, punishable by getting an extra expensive health insurance.
It gets complicated when you get a job that pays just a little too much, but not that much. If you already have social rental housing, you're lucky-ish. You'll lose your subsidies, but at least your rent will never rise above the 750 (adjusting upwards with inflation over time) mark.
You are egliable for social rent up to somewher about 120% of minimum wage, which would be an income of netto 2300 euros per month
Above that, if you're still living at home and are looking for a home, you're screwed. You're no longer eligable for social rental, because your income is too high.
Welcome to the free capitalist rental market. Expect your rent to be somewhere between 1200 and 2000 euros. Even if you only earn 2400 per month. No subsidies.
People earning just a few dimes under 40h minimum wage living in a social rental home are pretty lucky in this, as are people who earn a ton but have a social rental home from back when they didn't earn a ton.
EDIT: in answer to your other questions: building in the Netherlands is mostly prevented by EU nitrogen and CO2 emission restrictions. We need many more houses but we are not allowed to build them.
Asylum seekers that get granted residence get priority over natives in the social housing sector (which in my opinion is not unreasonable and fair. Asylum procedures take years. People granted residence becuse of valid asylum reasons already have spent years and years in internment camps, so yeah, give them a home).
Most expat workers are not egligable for social rent. They will need to find housing in the commercial sector.