I have a question
German French Brazilian (Portuguese) Spanish - which is better best for Chinese to learn? abd Which one more is most useful? Depends on you plans! But without fixed plans, Spanish is a much more used language, German and French are minor by comparison
Of those - Spanish for sure!
Spanish seems the easiest of the three for pronunciation, grammar and lexical similarities to English (lots of cognates). It's also probably the most useful because it's the second or third most spoken language in the world apart from English and Chinese. :)