if we assume that you will get the Unemployment benefit rate for people without dependent children, then you will receive (BEFORE TAX) DKK 15,279 per month. This equals DKK 183,348 per year.
Of the first DKK 46,000 kr.of these DKK 183,348 you pay no tax. This is what we in danish call your "personfradrag" (personal tax deduct for all people, before one have to start to pay tax).
Of the rest we can calculate your approximately tax percent for 2018 to be:
tax to the municipality you live in is in average 25%
tax (the lowest) to the Government is 11,15%
tax to the health system is 1%
tax to the National Church is 0,95%
So your brutto tax rate - depending on which municipality you are living in - will be 38.1%.
You can check the exact tax to your municipality here: http://www.skm.dk/skattetal/satser/kommuneskatter.
Your next question:
When you have been registered in your A-kasse with graduate rights/status, then it is correct as you say that you will be granted a 2 year period where you can collect benefits.
If you find temporary work, then you just write on your Unemployment Card (you do that online every month at your A-kass's website), the days/weeks you have worked in that month.
When you stop with a temporary job you continue from where you left in the consumption of the 2 year period. However it must be within the 3 year reference period. When you are a granted benefits ("Dagpenge"), you get a 2 year period, which must be used within 3 years (reference period).
However you must be aware that self-inflicted unemployment (meaning you quit the job yourself), will result in a 3 weeks quarantine with benefits.
You will off course not receive benefits for the days you work, but any kind of temporary work is good in two ways regarding your period with unemployment benefits after the temporary work has stopped.
You only use of the 2-year period when you actually get paid, so the hours/days you don't get benefits paid, is added to the other end. Moreover every worked hour will extend the 2-year period with 2 extra hours with Unemployment benefits ("Dagpenge").
Hope this help you. Otherwise you are welcome to comment here.
Anders Weber, www.a-kasser.dk