Thai food in Thailand is nowhere near as spicy as “Thai Spicy” or even “Hot” Thai food in the states, in my experience. Some places I went it approaches or slightly exceeds “Hot”, but on the whole I think the spiciness of Thai food is way overblown.
In my experience the spiciness levels are 1, 2, and 3 meaning 1 - 3 dried or fresh birdseye (or similar) red chilis. It’s pretty standardized and 3 is a hot but still pleasant level of spiciness. Thai people aren’t competing to see who can light their asshole on fire, they just want good food.













If that’s what’s holding you back, don’t worry. Thai people are very chill and kind on the whole. Also the economy is very dependent on tourism, so dealing with westerners is part of that. And, the US has not fucked Thailand over anywhere near as much as the surrounding countries (vietnam & cambodia, mostly, but even those folks are extremely gracious). People will appreciate you if you are kind, polite, and try to follow local customs.