Get really lazy after reaching 70% of udemy courses(nginx and bash atm)

[Brief-Wishbone9091]

i get super lazy once I reach around 70-80% of the udemy course and stop performing my best. I study well for the first 70% of my course, but once I reach 70%, I start to feel "know it all type" and feel unchallenged. Thus reducing my motivation to learn. How do I fix this issue?

Currently doing a course on bash scripting and nginx. Can you recommend some projects to work on to make this challenging but not too challenging?