Lack of faith in yourself/ low self-confidence

Its This is the main problem reason why we dont don't grasp ? follow your  our dreams. (you need to keep the personal pronouns consistent within the sentence)

We understimate ourselves yourself, consider dreams mush tall (?? I'm not sure what you wanted to say by 'mush tall')  and yourself are simply (?? I don't understand what you were trying to say here). We refuse to give up on (our/the) dreams even ?though we don't gove ourselves a chance to execute them (? is this what you wanted to say here) not giving yourself chance on it execution.

But by saying what if are saying "I will succeed!" and set  putting our mind to it yourself to then what our dream is real and achieve. we can achieve our dreams.

We are smiling and doing step up. Let uncertainty and by touch. -> (I'm not sure what you wanted to say here) ? Just smile and make your first step. Let go of your fears of uncertainty 
When you make the are doing first step, you understand which will second (?? I'm not sure what you wanted to say here-> ? you will know how to make the next one). And after road is built by itself (?? -> After that, it gets easier/ It gets easier with every step you make)



I hope this helps.
Nice 'pep talk', Aleksandra. 
I'm sorry but sometimes I didn't know what you tried to say.
Keep the personal pronouns consistent. You could use 1st person plural (= we), or 2nd (you). I think it would work better written in 2nd person (you).

Jo.

Hello! Nice thought, really inspiring. If you use we, then you have to use ourselves and not yourself, because that would refer to you (singular) and not we. Otherwise, change we in the subject and use you- yourself. You can write me back if you have any questions on my comments.

Lack of faith in yourself

Its It's the main problem why we dont don't  grasp your our dreams.

We underestimate yourself ourselves, consider dreams mush tall (did you mean too high?) and yourself are simply. (I didn't understand that, did you mean "and ourselves too simple"?). We refuse give up dream even not giving yourself chance on it execution.  I would say we give up our dreams without giving us the chance to accomplish them.

But what if are saying we say"I will succeed!" and set yourself ourselves to then what our dream is real and achieve. I think you meant something like "set ourselves to achieve our goal? The dream will become true."

We are smiling and doing taking one step up. Let uncertainty and by touch.
When you are doing first take the first step, you understand which one will be the second. And after then the road is built by itself.