( You can find athe video link here if you haven't seen it: https://langcorrect.com/journals/the-triple-happiness-of-hike/) ¶
¶
¶
It's a wild cave, which means there's no dedicated team to take care of it.

When we got there, Wwe found some trash on the ground, but we didn't have the tools to dispose of it, let alone carry it down the hill.

We can't be capitalized in the middle of a sentence. It's only if it's after a full stop.

Maybe Iit's only about 5% of the population, but still, we can't put an end to littering.

Only proper nouns like the name of countries, continents, person, days of the week, months and so on can the first letter be written in capital letter. Proper nouns are specific names and not generalized names like dog, shoe, street.
It is not after a full stop, so it's first letter can't be in capital letter.

In one of my previous entries, I talkedwrote about a cave on my last hike along a trail.

( You can find a video link here if you haven't seen it: https://langcorrect.com/journals/the-triple-happiness-of-hike/) ¶
¶
It's a wild cave¶
¶
It was a natural cave outside of a park, which means there's no dedicated team to takes care of it.

When we got there, Wwe found some trash on the ground, but. However, we didn't have the tools to dispose of it, let alone carry it down the hill.

ButHowever, I still feel it's wrongbad about the litter.

It's seem unfair to leave those pieces of trash in the cave and let, making the villagers do the extra work.

Maybe It's only about 5% of the population, but still, we can'thikers are thoughtless, but we need to put an end to such littering.

SoAs a result, I decided to help the villagers build a garbage collection program as a part of a game project.

I have never hiked to any wild areas outside China, so it's totally unknown to medon't how other people in other areas deal with this.

I nNeed sSome aAdvice

In one of my previous entries, I talked about a cave on my last hike trailthat I encountered on my last hike (You can find a video link here if you haven't seen it: https://langcorrect.com/journals/the-triple-happiness-of-hike/).

( You can find a video link here if you haven't seen it: https://langcorrect.com/journals/the-triple-happiness-of-hike/) ¶
¶
It's a wild cave, which means there's no dedicated team to take care of it.

When we got there, Wwe found some trash on the ground, but we didn't have the tools to dispose of itthem, let alone carry ithem down the hill.

Luckily, that area belongs to a small village, so villagers will come to clean ithem in their spare time.

But, I still feel it's wrong.

It's unfair to leave those pieces of trash in the cave, and letmake the villagers do extra work.

Edited the phrase to sound more natural.

So, I decided to help the villagers build a garbage collection program as a game project.

Andlso, if you have seen some successful solutions to relatedsimilar problems, please share them with me.

I have never hiked to any wild area outside China, so it's totalcompletely unknown to me.

In one of my previous entries, I talked about a cave I found on my last hike trail.

This sentence is something a native might say, however it looks a little unnatural when written down. It suggests that cave was *on* the trail which I don't think is what you meant, especially since your post said it's a "wild cave".

An alternative:
"I talked about a cave just off the trail on my last hike"

( You can find a video link here if you haven't seen it: https://langcorrect.com/journals/the-triple-happiness-of-hike/) ¶
¶
¶
It's a wild cave, which means there's no dedicated team to take care of it.

I'm not sure if "wild cave" is the right term. I tried searching online but couldn't find a suitable alternative.

The sentence is fine and I understood you perfectly.

When we got there, Wwe found some trash on the ground, but we didn't have the tools to dispose of it, let alonethere was nowhere to dispose of it nor did we have anything to use to carry it back down the hill.

I'm not sure what "tool" would be used to dispose of trash?

Luckily, thate area belongs to a small village, so and the villagers willoften come to clean it in their spare time.

It's unfair to leave those pieces of trash in the cave and lexpect the villagers do extrato do the cleanup work.

In the meantime, I have to admit that some guys in themy hike team are shameless.

"In the meantime" is not appropriate in this context.

If you mean that some hikers in the entire population are shameless, you could say:
"I have to admit that some people in the hiking community are shameless"

Maybe It'sIt may only be about 5% of the population, but we still, we can't put an end to littering.

The word choice of "population" is fine but a more natural word might be "community".

So, I decided to help the villagers builddevelop a garbage collection program as part of a game project.

The project plan hasn't been finishcompleted yet.

I have never hiked to any wild area outside of China, so it' and best practice internationally is totally unknown to me.

I understand the idea of the sentence. However, the sentence is not natural because you did not specify *what* is unknown to you.