The morning

Today we have experienced a first really sunny day in the city where I live. Since the autumn have (has) come, the days were (have been) extremely miserable. Everything was grey and shabby outside in my view: (the) buildings had a colour of a steel, taupe trees, nearly dark roads and the plumbeous sky… But everything was (had) changed on October,1. When I had opened my eyes, I have felt an amazing warmth with (on) my cheek, because of the incredible sunshining(e). A new day have (has) begun! The day, which have (has) brought (given) me the energy for doing (to do) great things and making (make) important decisions...

 

Nice. Just remember the conjugations of "To have" :)

I have               

You have

He/She/It has 

We have

You guys have

They have

  

The morning

Today we have [simple past tense, not perfect tense required] experienced a the [the "first" is definite and requires the definite article] first really sunny day in the city where I live. Since the autumn have has [singular] come, the days were extremely miserable. Everything was grey and shabby outside in my view: buildings had a steel colour, the trees were taupe, the roads were nearly dark and the sky was overcast [parallelism, also plumbeous is somewhat unusual vocabulary, "overcast" is sufficient and better.]… But everything was [no need for passive voice] changed on October 1st. When I had opened [simple past, not pluperfect tense is necessary] my eyes, I have [no need for perfect tense again] felt an amazing warmth with on my cheeks, because of the incredible sunshine [conventional vocabulary use]. A new day have has [singular] begun! This change of weather has given [more precise and conventional vocabulary] me the energy for doing great things and making important decisions...

The morning

Today we have experienced a the first really sunny day in the city where I live. Since the autumn has come, the days were have been extremely miserable. Everything was grey and shabby outside in my view: buildings had a the colour of a steel, taupe trees, nearly dark roads and the plumbeous sky… But everything was changed on October 1st . When I had opened my eyes, I have felt an amazing warmth with on my cheek, because of the incredible shining sun. A new day has begun! The day, which has brought me the energy for doing great things and making important decisions...