Does the 'r' in ĵurnalo have to be rolled? I'm an English native and finding it almost impossible to pronounce.
I don't think it has to be as hard as it is in the audio, but it is a tapped or trilled R similar to the R in Spanish and Italian. It sounds a lot like the double T in 'butter'
You can train your tongue to do it. Try making a sound like a purring cat. The rolling of rs is very similar and it's good practice :)
I cannot roll my Rs either. I can pronounce tones in Mandarin but rolling Rs is beyond my ability.
Many speakers come from France and Germany, many of them can't roll /r/ too, so the large variety of /r/ variations is acceptable, don't worry :)
How to pronounce "ĵ" ? is it pronounced like "g", as in George or it's pronounced like the French "je" ?
Like the French "je"! It's the "zh" sound you find in the middle of words like "measure" or "leisure". :)
(The "g" in George is the sound for "ĝ".)
Another way to think about ĵ is that it is a voiced version of ŝ (where ŝ is like the English sh).