So, is speaking in Japanese difficult? No, it's not. In fact, it's very easy and if you're an English speaker, you should be able to pronounce correctly every sound of the alphabet.
Most Japanese sounds have vowels in them, and they're pretty much the same as in English. The majority of the sounds consist of a consonant and a vowel. As for how to pronounce the vowels? It's easy:
A = pronounced "ah"
I = pronounced "ee"
U = pronounced "ooh"
E = pronounced "eh"
O = pronounced "oh"
N = it's a hard "nn" sound
For consonants and vowels, they're also easy. "Ka" is simply pronounced "kah" and "se" is simply pronounced "seh" like how the vowels are pronounced. They just have a consonant in front.
Worried about the tone? Don't worry. Tone is different across different areas, regions, age groups, etc. and so it would be best to just try and imitate what you hear. Just keep in mind that there are two tones: low and high. That's it. And each sound is pronounced with the same amount of stress and duration (a sound can get a longer duration with the addition of another character, but we'll discuss this in the upcoming posts). As long as you get this down, speaking Japanese will be simple. It also helps to listen to Japanese people speak and try to imitate what they say to understand the flow of speech.