Trying to get NIE/Residencia and become Autonomo on the magic roundabout

Well, was it all a dream or a nightmare?

Can anyone help?

I want an NIE/Residencia card/number. I have no job. I came to teach English. I am told by the functionario I need private health and money to support myself. I have enough money in my U.K account, but I don't want to transfer because of the exchange rate. I am denied NIE etc.

I want to become self-employed. I think I need the NIE number to do this. I want to pay fing tax. I don't want their money, but they don't want mine. What can I do?

The most important thing at the moment is, should I just start looking for students and working, keep records, charge IVA, give out receipts or whatever or will Uncle Manuel come looking to milk my money belt with a fine?

I am baffled at the moment.

Any help would be greatly appreciated.