Hello, I am leaving my current school and going to work at an international school. Are the krusupa and TLC course different or can I take the course at any place it is offered?

This is what the International Schools Association of Thailand (ISAT) writes on its website.

Teaching License

For teachers, one of the requirements for a work permit is a Thai teaching license. Many teachers at international schools already have a teaching license in their home country so the process of obtaining a Thai license is not complicated. Teachers who do not have a teaching license in their home country will need to show appropriate qualifications to obtain one in Thailand. Before being issued with a license all teachers are required to complete a 20-hour workshop on Thai language and culture,and professional conduct for teachers. For international schools, this workshop is conducted by the employing school according to training designed by ISAT. If training sessions are not scheduled for soon after your arrival, you can still obtain a work permit and commence teaching by providing a letter issued by ????????? stating that you will complete the training within a specific period. It is illegal in Thailand for foreigners to work in any capacity without first obtaining a work permit. Work permits are usually issued for a specified employer. Working for another employer is a violation of Thai Labour Law. All foreigners in Thailand are subject to the laws of the Kingdom of Thailand. Broadly speaking, these laws probably do not differ greatly from those of your home country with the exception of Thai laws relating to defamation of the monarchy or royal family.

http://www.isat.or.th/index.php?option=com_content&view=article&id=58&Itemid=125

Are the krusupa and TLC course different or can I take the course at any place it is offered?

It's the same and you can do it where ever you want.

I'm surprised to see an international school that doesn't offer it at the school or organize it for you.

Do you have to pay for it yourself?

I'm not sure. I hope they will take care of it. They are supposed to let me know today.