Translation:There is no money.
it means "so" or "therefore". https://jisho.org/word/%E3%81%A7%E3%81%99%E3%81%8B%E3%82%89
Consider が as a main actor and は as a supporting actor. As such, use が when you want to emphasize something. In this case, you are emphasizing the fact that you have no money, so が should be used after お金.
If you want to use は here, you can say something like "I don't have money but I have xxx instead". Here money is used as a supporting role to emphasize xxx, so you want to use は for money and が for xxx.
I don't have money, but I have you.
From there, you can expand on it and twist the meaning a bit to amuse yourself.
Even though I don't have any money, I'm glad to be without you.
The kanji does mean gold, but by itself it's usually read as かね (usually also with the honorific お at the start) and means money. According to jisho.org without the お it can be read as きん and mean gold (so not in the case of this sentence since it has the お), but I'd recommend using 黄金 (おうごん, literally 'yellow gold') to differentiate, especially in written Japanese where people can't tell what pronunciation you intend for the single kanji.