Hello everyone! I tried a Barn Owl, I started with 4 reference images and the tried the last one on my own.

I am not completely sure but I guess you are starting the sketch from the head. That might lead to magnifying effect for the head and the rest of the body looking small. Next time you draw try drawing a hand first and choose a line from that hand as a scale to compare and draw other parts of the subject. Comparing other lines from one line while drawing helps us draw better proportionate sketches. Try these two things and let me know if they have helped 😉👍 have fun.