Is it difficult to learn Greek?

I've been reading a Teach Yourself series book where they explain a very easy way to learn Portuguese. I think it's extremely easy for me because I'm a native Spanish speaker so those are very similar. The thing is, I just had a look at the Greek version and it's madness!!! The guy who invented that language must had been crazy or had issues, I don't know!!!

chronicles chap 2 verse 31

skillful to work in gold, silver ,brass and iron, stone and in timber, in (purple in blue and in fine linen and in crimson.)
translate the parts in commas
i believe its in Reference to the Phoenicians. but i want to know if the word Purple is written as phonik in the greek version.

Me and my friend are very interested in finding words in the Greek language but we've searched for endless hours without prevail as to how you would write "Leader" or "Commander" in Greek. ηγέτης and Dioiki̱tí̱s is the closest I could find but I would really appreciate it if anybody could tell me how to pronounce "Leader" and "Commander" in Greek, as well as to how it would be spelled in Greek and how it would be spelled in English from the Greek version of it. Please and thank you.

Can you translate and write my name in Greek?

It`s Nicholas Joseph.
Can you write it with Greek letters too (both the En version, but more the Greek version if you want.)
And if you could help me with the pronounciation, too.

Can someone translate the greek phrase that was told to spartan soldier by their mother before departure to war. "Come back with your sheild or on it"?
preferbally a Modern Greek translation and/or the Ancient Greek version that would have been actually used?