What documents are required to switch to an ED Visa in Thailand after a Covid extension?

Hello everyone!

I came to Thailand in July 2021 on an ED visa as I did an exchange study program at a school here. Because that ended in December, I had to switch to Covid extension which I am currently on now. As I am starting an internship for a company here soon, which is also part of my study program from abroad, I would have to switch to ED Visa again.

I wanted to ask if you know whether there are other documents needed for immigration other than letters of acceptance from the company here/my university abroad? They also said a letter from my embassy, but apparently they do not offer these consular services. Do you think this will pose a problem when I go apply for the visa?

Thanks in advance for all the information!