What are the steps to obtain an ED visa for Muay Thai in Thailand, and how does it differ from a tourist visa regarding application limits?

I would look at schools that do the visa for you... There is likely an additional charge or its part of the cost. If you're confused now you will most certainly be confused when trying something like and ED visa. Thai visas/Thai government is freaking nuts, in part because I don't speak the language, in part because the Thai government is little goofy (all governments really).

No limit for tourist visas. There is a limit on visa exemption by land (entering Thailand without visa).

Thai language ed visa not expensive, muay thai expensive bro

Stop

Rethink

Get a Thai Language Education visa

First you find a school that is willing to sponsor you for the visa. You talk to the school and find out their procedure. Do they want you to apply for your visa at the embassy in your home country before you travel to Thailand, or do they want you to come as a tourist and convert to the ED visa in Thailand?

If they want you to apply first then you go online and apply for the visa with the documents the school sends you.

If they want you to travel to Thailand first, then you go to Thailand and follow the instructions of the school. Usually they will need you to report to the school shortly after arrival so they can take copies of your passport and your entry stamp so they can submit them to the Ministry of Education for approval. Once it's approved then they give you documents to take to immigration to apply for the visa conversion. It can take multiple weeks to get all of this done and you need at least 15-21 days left on your stay in Thailand to apply for the ED visa, so you need to move quickly once you arrive.