Question

不知道这段话用英语表达有没问题呢？

Perhaps the youth we missed, is immature, but also our sentimental. Perhaps we are no longer young, and finally understand tolerance, the person whom you love most has been missed early.
也许，青春里的错过，是我们不成熟，也是我们的青涩。也许，不再年轻的我们，终于懂了宽容，最爱的那个人却早已错过。

Answer 1

Perhaps what we missed in youth is not only our immaturity but also our callowness. Maybe we, who are no longer young, finally learn how to be lenient, but the most beloved one has been gone for a long time.
【英语似乎比较忌讳重复用同一个词，以上仅供参考】
或者：Perhaps what we let slip in youth is not only our immaturity but also our callowness/inexperience. Maybe we, who are no longer young, finally learn how to be lenient, but the most beloved was missed long time ago.