It sounds like you're looking for the "Italijanski bez muke" (Italian Without Toil / Assimil) PDF and asking if the content inside is actually useful for learning Italian.
Here is the direct answer to your question about its usefulness, followed by practical guidance on obtaining the material legally.
Solution: Supplement with modern apps (Duolingo, Linq) for contemporary slang. The grammar and core vocabulary are timeless.
Assimil’s first wave is passive. For 5-6 weeks, your only job is:
Pro tip: Upload the PDF to a cloud service like Google Drive. Open it on your phone. Listen to the audio on headphones during your commute. This is how the PDF works on the go.
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