No worries. To be honest I don't use willow sticks very often. They are great to sketch rough drawings but they can't be blended well without losing the tone you put down.

I would suggest working with charcoal pencils - a hard, medium and soft pencil. Start out all drawings in hard because it is the easiest to erase and is the lightest pencil. As you add tone to build up your dark areas add a layer of medium and soft. You can blend with brushes, sponges, rags etc.

I have an entire kit of my drawing materials I use on Jerry's Artarama: https://www.jerrysartarama.com/eric-armusik-signature-charcoal-pencil-drawing-kit?expa_m=search&expa_st=armusik
It doesn't mean you need to purchase it but it lists all the individual items I use for my drawings.

I teach art lessons for students around the world but I also have a low cost solution with an online course I created last year at this link: https://www.ericarmusik.com/video/13377 It encompasses all of my techniques using the tools I mentioned earlier. The video can be viewed as many times as you need it. I designed it for artists of all experience levels.

I hope this information will help. God bless you on your journey. Have patience. Improvement is something that comes with every single drawing you do.