I study English

You are naming the project which makes "project" specific. You should add "the" in front of project for this reason.

In this project learn many people.

"learn many people" is correct in many languages but in English we always talk about who does the action first. In English you should say "many people learn"

They study different foreign languages. Everyone decides

how many time per day to learn language.

You have two choices here "How many times" (time is countable with an "s") or "how much time" ("time" is uncountable no "s").  When you say "How many time" You are confusing the two of them.

We actively use open sources in web.

I'm not exactly sure what you're saying here but I think you want to describe HOW you use. Since you're describing an action, you should use the adverb form "actively"

Curators helps us

Here is a simple rule to remember he/she/it = S (forget about third person second person first person...that's too confusing) Curators would be substituted with "they" means there is no "s". You should say "Curators help us..."

and give us a interesting tasks.

This phrase is illogical because a=1 and the "s" on tasks means .2,3,4..... You probably receive more than one task so the correct phrase would be "and give us interesting tasks..."

I learn listening, reading, writing and speaking English. I want to listen, speak and write English confidently.

Every day which share with other student their success.

In this sentence your verb is "share". We always need to say who is doing this action. In this sentence you're not saying who is doing the action.

We share

With a verb like "share" it's best to state "what" immediately after. We share (what)

We share our success

Because the exchange is mutual (you share with them and they share with you..every shares together) use each other

We share our success with each other

They give us a motivation to learn more.

In this case motivation is a concept and not a countable noun, eliminate "a" (remember "a" means "1" you can't count an uncountable noun.)

They give us motivation