That you cannot please everyone.
No matter how good of a person you are, there will always be someone who would find something bad in you. If this person comes, never force yourself to like them. You are special; there are people out there who knows you very well and appreciates you just the way you are.
That people come and go.
I value friendship a lot, and I'm always afraid of losing anyone. However, I've come to realize that we must accept that people change, that times change. And that when people walk out of your life, it does not always mean that something's wrong about you. Sometimes, it's just that the bond isn't as strong anymore. That's fine. We just have to be thankful that we've made great memories with this person.
That things do not always go the way we planned them to.
There's this thing we call fate. What is fated to happen will happen and what is not will not, no matter how hard we try. It can get frustrating, yes, but we always have to be reminded that everything happens according to God's plan. His plan will always be better than ours. So if things get messy, trust that whatever happens, will always be for the better.
That as much as it is important to think of our future, we must never forget how to live in the present.
Sometimes, when we're stressing so much for what tomorrow brings, we forget to live for today. While it is acceptable and totally normal to plan and act for our future, we must not sacrifice the memories we should be creating now. We must not forget how to enjoy and live life to the fullest. When we get there in the future, we will definitely look back on how we all lived, and we wouldn't want to remember nothing just because we actually forgot to live in the moment.
That it is never too early (or too late) to try to do things.
One of the best things about being young is that there are a lot of opportunities and activities we can grab. We should not be afraid to try things that interest us because as they say, we'll never know unless we try. I've been the same person, playing it safe, sticking to my routine, and I always use the lack of time as an excuse. But hey, if there's a will, there's a way. Turns out I was just afraid I would not be good at it. But I realized that it does not actually matter whether or not you'll be good at it, what's important is that you tried it and that it will never have to remain just a What If in the future.
That love does not always need to be reciprocated.
It's not about being a martyr. It's about being mature. It's a form of selflessness; it's accepting that not all people can reciprocate the love you give, and understanding that does not mean they don't appreciate it. The fact that they acknowledge it should be fine with you, not because you don't love yourself but because you understand what love really means—it's being contented with what other people can give and not making that affect the amount of love you give away.
That it's not geeky to be concerned with world issues but rather, normal.
While there's nothing wrong with being a geek, world issues shouldn't be considered as those that only a few intellectuals would and should care about. We're ALL actually supposed to care for the world. People have this stereotype that if you know the Sustainable Development Goals (just an example), you're an overly intelligent person. But we should actually be involved in this, not just the scholars and the intellectuals, and there should be some way we could tell this to people.
That it's okay to understand things just now.
Probably all these things I have listed are already general truths, common life knowledge. But you won't really appreciate and understand the essence of these unless you encounter real-life scenarios to prove them. And if you still don't appreciate these things big time, fret not. I'm quite sure life has its own way of making you appreciate these things. Just keep going.