1. I don't think it is wise to come to either AUS or USA unprepared. It's such a waste of time and money (for language school). With some effort I believe you can do better than that (TOEFL).
2. Albeit your low GPA, there will always be schools in USA or even in Chicago that will accept you. Don't worry about that.
3. I assume your family will support for tuition fee right ? If so, it is possible to work your way (in restaurant, if you can find one) to support yourself for monthly income. But then again, it's too time-consuming, exhausting and you need more time for your studies provided that your English is not well-established :-). It is always a misguided myth that one's English will be improved just because one move from Thailand to English-speaking country. And it won't be the case, if you have to work in Thai restaurant for the most of your time.
4. I really encourage you to work in Thailand and prepare for TOEFL for a year or more before coming to USA. It is much more worthwhile. Knowing that MBA program values work experience so dearly, I don't see the point or any advantages of being here early while lacking preparation .In the end, you are the one who will suffer most.
5. One of the reasons I'm telling this to you is because a friend of mine who once thought like this now is suffering so much. He has been here for almost a year, enrolling in language school and taking toefl for several times. So far, it's still unsuccessful and he really regrets his decision but he just can't turn his back. The sense of guilty for wasting his parents' hard earned money is overwhelming. So, please think twice about coming here if you are not ready.
เราว่าที่ AUS หรือ USA ก็น่าจะเหมือนกันนะ เพื่อนเราเรียนที่ AUS ทำงานที่ร้านไทย ก็มีเงินเก็บพอสมควร เห็นว่ารายได้ตกอยู่ที่ประมาณ AUD$5 ต่อชม ไม่รวมทิป ค่าครองชีพก็ถูกว่า USA กะ UK ก็เก็บเงินได้นะคะ ...
โดยส่วนตัวอยู่ UK มา 18 เดือนแล้ว ทำงานกะฝาหรั่ง ไม่ได้ทำร้านอาหารไทย ... วันก่อนซุป บอกว่า I think you'd better speak more English, you are here for 18 months ... but your english is not really much improve ... เพราะงั้นการที่มาอยุ่ที่นี่ไม่ได้หมายความว่าภาษา จะดีขึ้นทันตานะคะ (ตอนมา IELTS อยู่ที่ 7 อ่ะ)
I strongly recommend you becuase I 'm one who applied MBA.In my idea Professors who teach in graduate school assume that one who takes their classes should have adequate skills. I got 23 points in part listening. I don't think 23 is good but it seem to be ok at first. Now I just know that I can't stand here. Everything is harder than I thought. I 'm not sure for the idea of the others. I wanna share some experience for you. I think english course is necessary because you 'll have sometime to adjust yourself ,moreover you 'll have the opportunities to choose the best way for yourself. You should not believe me at all. Read all comments then make the decision. If you want some help please post your email here.
It depends on your decision. However, I would like to warn you if you want to study English language in overseas. First, you will spend much more money than passing TOELF or IELTS. Second, it is not exactly sure that you can pass the English course after six months in Australia. I also had the condition offer from University of Wollongong. It is extremely easy to get it because I did the same way as you via agent. After that I have studied direct entry course for three months. However, I failed and could not study in uni. Finally, I came back to Thailand and tried to re-take IELTS until I can get 6. Now I'm studying in UK. I'm so sorry that I can not suggest the ways to improve your TOELF scores because I never take it. P.S. Hopefully, you can get the TOELF score 213 soon.