anyone know a website of images i can sketch for practice?

I have a question. Since this is a continuation of sketching, do I still have to structure the sketch with boxes and other shapes before using tapered lines?

Are these strokes good?

Here's an attempt. But I don't know how to draw the whole thing in individual lines

Are my ellipses right?

How's would this be?

I'm a complete beginner. Is this kinda good?