I feel your pain. I actually began studying Spanish decades ago myself, in college, but forgot most of it because I did not keep it up. Last year I started using DuoLingo to relearn Spanish and it took me 9 months to complete the tree ( https://www.duolingo.com/comment/5980811 ). I do not consider myself fluent yet, but at least now I have a strong foundation to work off of while really learning the language. Hopefully one day I will be competent in it. Good luck to you as well.
My husband has just pointed out to me that the "Duolingo method" is similar to taking driving lessons.
Although there is obviously no formal competency test on the way, it drills you enough to give you confidence to talk to native Spanish speakers and read Spanish etc. This gets you "on the road" to finally gain the experience required.
I've not covered that section in "Verbs: Present Perfect" yet but the only thing that strikes me as odd is the singular third person "ha" here. Obviously it is agreeing with the singular "esto" and "nos"/"us" is just extra info. "Esto ha llevado meses" = "This has taken months" according to google translator.
Llevar is a very common way to express time.
I suspect TilEulenspiegel is talking about something more general. The Argentinian s, y, z, and ll do sound french to me, but, for example, on an ad on TV, I hear what sounds like "jamanos ja" for "llamanos ya" (call us right now). I don't hear that J sound (like in English) in European spanish, but I sure hear it all over in New World spanish.