Why does Allah allow such unequal starts in life if He is just?

Assalamu alaikum everyone. I'm not a believer myself, but lately I've been curious about Islam and there's one thing I just can't wrap my head around. I'd love to hear what practicing Muslims think. So, Islam says Allah is perfectly fair. But when I see how different people's lives can be from birth, it’s hard for me to see that fairness. I get that those who suffer here will be rewarded in Jannah. My question is: why isn't there more justice in this life too? Some people have it easy and go to Paradise, while others struggle nonstop and still end up in Paradise. Let me paint a picture of three imaginary people: - Brother/Sister A: Born healthy into a good family, life is comfortable. - Brother/Sister B: Born with a condition like severe scoliosis, causing constant pain and making life tough. - Brother/Sister C: Born with health problems similar to B. Now imagine their lives: - A: Has a smooth life, no major health issues. They find confidence, marry, raise a family, and live happily. They’re devout and die with faith, entering Jannah. - B: Endures chronic pain daily, their appearance takes a hit, and they never find a spouse despite trying. But they stay patient and hold onto their deen, and also get Jannah. - C: Faces the same struggles as B. But this time, the hardship breaks them-they lose their iman, drift from Allah, and end up in Hell. Here’s where my brain gets stuck. A and B both get the same eternal reward, but A had a way better life on Earth. B suffered for years first. How is that fair? And with A vs. C, you could say C chose their path. But what if their suffering pushed them harder toward losing faith? And who’s to say A would’ve stayed faithful if they went through the same trials? I’m not trying to attack Islam-I genuinely want to understand this. If anyone has clear answers or resources, I’m all ears. Jazakum Allahu khairan.