Will my allowance be enough to survive Amman's expenses?

Hello there,
I think JD 300 will be extremely tight. You will face difficulty to manage to the  end of the month. I assume that you are a single kne person. My advice is to find a cheaper or shared rent and save on that. Amman is one of the most expensive cities in the Middle East.

I second that.
It's to much spending your half salary to housing. It's not worth it.
Even you do, you're be fine but it depends totally on your lifestyle and your social status.
Nightlife is expensive too.

Food and transportation yes, going out probably no.  Two of us lived on less than your monthly allowance for two years.  While we had enough for basic things, going out for dinner was a once a month event.  That is about an average salary in Jordan, a lot of people make even less.

Would be so hard to live with this amount of money. You won't be able to do a lot.

Your budget is a bit tight.try to look fir accommodation near officers that you cam walk to office .
Ensure you can.cook from.home and pack your lunch instead of having it in restaurants.only eat out once in a while.then the 300JOD will be able to push you for a whole month

From my experience, yes it will be enough for you.For one person living on budget,not eating from outside , cooking your meals ,buy your weekly grocery from hyper markets.You  can even go out with friends once or twice.Be Smart how to spend your allowance on ,maybe take advantage of offers of food, clothes,save money from bills like electricity,water,if you find a place to live close to your work, try to live like locals not as a foreigner or visitor.
Cheers