This quote is about facing challenges by yourself. "The hardest walk is walking alone but it's also the walk that makes you the strongest" means that even though it's tough to go through difficult times on your own, it can make you really strong and brave.
Imagine you're climbing a big hill. "The hardest walk is walking alone but it's also the walk that makes you the strongest" is like saying when you climb the hill by yourself, it's tough, but you become very strong.
In simple words, this quote tells us that facing tough times alone might be hard, but it can make us really tough and strong in the end. It's like going through a challenging journey that helps us become braver and more resilient.