It's quite difficult. You will need a permit issued through the Thai Department of Land Transport and a guide. You would need to contact a Thai travel agent with a tour licence to do the paperwork, which includes a temporary Thai licence in the province of entry if all you have is a Chinese driver's licence.

Overall it's going to be very expensive. Today coincidentally marks the second anniversary of when the rules first went into effect; about 6 months later there were some amendments, which allowed driving outside the province entered but a guide and lead vehicle became mandatory, making driving into Thailand from China feasible only for those driving in convoys.

As the Brazilian Real is not a major currency, not to mention that China is on the opposite side of the world to Brazil, you'll struggle to find it anywhere in China. Maybe in Hong Kong, maybe, but not the mainland for sure.

The following currencies can be exchanged in China: USD, EUR, CHF, GBP, JPY, AUD, NZD, THB, SGD, HKD, MYR. A few others such as Indian, Lao, Vietnamese, Russian, middle Eastern, South African and Scandinavian currencies should also be OK to exchange at some banks and in the case of Lao and Vietnamese currencies, in Guangxi and Yunnan provinces. All other currencies are virtually impossible to exchange or purchase so don't even try.

@HFCAMPO, that's interesting, because I've received student discounts in China based on possessing a student card from another country or someone in my traveling party has.

However, many tourist attractions may only accept local student cards, it depends on their policy. That is to say that both local and international students can use them, but they have to be studying at a local Chinese university/college.

It's easy enough to book a connecting flight on Malaysia Airlines, THAI or Cathay Pacific to get to Paris from Kunming. Daily (or at least regular flights most days of the week) connect Kunming with these cities and then from there daily or sometimes multiple daily flights connect to Paris.

Umm really hard to say at the moment, but perhaps Brazil? Then again there have been some upsets so far including Switzerland beating Ecuador and the USA beating Ghana, so it's anyone's guess at this point.