There's nothing about basic income that prevents working. In general, having more money gives people better options. For example, it can make it more practical to go back to school, or to take a rewarding but low-paying job such as teaching.

On the margin, there may be people who choose not to work. For example, they may decide that staying home to raise the kids is a better choice than a job that's barely worth it. Businesses might need to pay people somewhat more or treat their employees somewhat better to fill positions. I don't see how this is a bad thing.