It is just as challenging as other engineering fields. However, it is a highly interesting field to research and work in. Once you go into it and begin experimenting with the tools and approaches, you might find it more fascinating than other fields of study. One fact that is for sure is that ML or any field of Data Science requires the right amount of time to understand it as a concept, implement it, and finally to master it. Difficulty varies from person to person.
If you are interested in learning about this technology then I suggest you to go for the Intellipaat Machine Learning online Course.
Before that do check out this amazing machine learning course video by experts at Intellipaat -