Since you are guaranteed to make mistakes out there, why not learn vicariously from other thru-hikers in order to limit your learning curve.
Thru-Hiking Risk Assessment and Decision Making
McAfee Knob Day Hike Along the Appalachian Trail — Melanin Base Camp
The Top 5 Most Common Thru-Hiker Mistakes
Hiking Clothes for 2020 Hike Safe, Warm and Comfortable
How the Appalachian Trail became the phenomenon it is today
Most Common Mistakes Thru-hikers Make – One of Seven Project
Six mistakes I made while hiking the Appalachian Trail (and why YOU should avoid them!)
Most Common Mistakes Thru-hikers Make – One of Seven Project
The World's Most Dangerous Hikes