Not for a PhD, but I had similar feelings about supervision for my internship. When I was starting off, it was hard for me to tell how much initiative I need to

Not for a PhD, but I had similar feelings about supervision for my internship. When I was starting off, it was hard for me to tell how much initiative I need to take versus how much my mentor should guide me. He was always busy and at times I felt like there was no need for the role I was hired for. In hindsight, I feel like my mentor should have guided me a lot more than he did. But it's hard to know that when you're just starting off, and you tend to blame yourself for not taking enough initiative (even if you are).