musicaneo.comは安全ですか？

This site is a scam that is generally selling public domain works from imslp (everything that is uploaded to imslp is free and free of copyright terms) and charging people. They can also be seen selling non-public domain works without work's copyright holders approval. You can generally find what they're selling on the internet with some research and patience. And if you cannot find what you are looking for, do yourself a favor and buy it somewhere else. There also have been reports that customers don't actually receive what they've paid for etc. Bottom line, stay away from this website.