Natural wWonder in mMy oOwn cCountry of Bangladesh

Most words in titles start with an uppercase letter

Honesty, ¶
I said, that's I known on my own county of Bangladesh.

This county's most natural wonders are coxce'sbazar, potanga seabeach, selyet Japlong, Bagerhat Khulna exctra.Exc Actually I've only visited ¶
Only ¶
piranha sea beach.

I think you meant "actually" but I'm not sure. Also that's amazing I love piranhas

This beach had two many parts theirsre.

Their is a pronoun meaning belonging to them. There is a location. Also, you either meant to say "too many" (meaning a lot) or "two main" (there are 2 parts that most people go to)

Mostly common part is the beach long area, and the waves are peachefull.

"The waves are peaceful" could be a sentence by itself, so you need to add a comma before "and"

We are try to go arounding this whole area's.

"whole" means entire while "hole" means like a hole in your shirt or the ground

Firstf of all we are bookinged a sea bord and than arrived at it.

We are six people arived theira group of six people.

We are looked at the sea when we seeaw some big ship's Fisherman catch fishes.

The plural of fish is fish, it is confusing sorry.

We were surprised of how many types of fish we saw whenduring our time is over bookingat the sea board. I was fefelt board thanred, so we decided to refreshing our mind we ars. We jumpsed over the waters, went swimming, and playing wed. We feelslt relaxed.

"bored" is the emotion "board" is a thing. You had a run-on sentence (meaning it is to long to be a sentence), so I tried to split it up where I thought was best.

We are changed our cloathes.

You are speaking about something that happened in the past, so you have to use the past tense.

We are visited some shops to buy little bitsthing, and we are going a foodwent to a restaureants that's amazing t. They are suserved many type of's food.

We eat, and it's setiespiedly.

I don't know what word you meant to say here, sorry.

No mThat's all fore today's i. I am waiting for you response.

Thank you so myuch for helping me and my journey.

Honestly, ¶
I said, that's I known onew my own county of Bangladesh.

I'm not sure what you wanted to say here :/
Alternative: Honestly, I can only share what I know about my own country, Bangladesh

This county's most famous natural wonders are cCoxce'sb’s Bazar, potanga sea beach, selyet JaplongSajek Valley, Bagerhat -Khulna exctra.Excually Itc. however I have visited ¶
O¶
only piranha sea beach.

This beach hads two mainy parts theirs.

M The mostly common parea is the beach long area and, where the waves are peachefull.

We are try to aroundingexplode this whole area's.

Firstf of all we are bookinged a sea bord and than arived it.

We awere six people arrived theirat the beach .

We awere looking at the sea when we seeaw some big ship's Fwith fishermaen on them catching fishes.

We were surprised by many types of fishes we saw w. When our time is over booking sea board I was feel board thanbooking time was over, I felt bored, so we decided to refreshing our mind we are jumps overselves by jumping into the waters, swimming, and playing we feels relaxed.

We are changed our cloathes.

We are visited some shops, buy little bits and we are going a foodought souvenirs and went to a restaureants that'. That was amazing they are suerved many types of's food.

We eate it's setiespied happily.

No mThat's all fore today's, i am waiting for your response.

Thank you so myuch for helping me improve my writing about my journey.