What is the suitable & easily understandable programming language for API?

I am optimistic about that I will be able to learn how to develop API. Here is lot of platforms so please help me by knowing the suitable language/platform for API. FYI, my dream is to be a well trained developer under only one platform & it will be related with Cryptos. So my Seniors, plz help me to get some TIPs to learn early and easily understandable API code platform & the way of learning as well as development. Kindly consider my request as New one learner. https://www.sololearn.com/discuss/1316935/?ref=app https://www.sololearn.com/discuss/1926810/?ref=app https://www.sololearn.com/discuss/1927953/?ref=app