"I want to go online and listen to music."
I think the problem is that 和 (hé) doesn't work exactly the same as English "and". The basic rule of 和 is that it usually only links two nouns-- for example: 我喝水和咖啡 (I drink water AND coffee). There are some complicated exceptions, but up to this point in the course, I feel like duolingo is enforcing the noun-to-noun only rule.
Here are some articles from 'Chinese Grammar Wiki' if you want further explanation/examples: