One day I have spoken with my friends to goabout going somewhere asfor a picnic, so we wer. We planned to go to Dubai in the uUnited aArab Emariirates.

“my friends” is not incorrect, but less common.
“So, we planned…” is not incorrect, but less common

In tThe next day we have goingleft with towo cars, because of number of my friends arI have more than 6 personfriends.

Or you could say, “because 6 of us were going.”

One day I have spoken with my friends to goabout going somewhere asto have a picnic, so we were planned to go Dubai in the uUnited aArab Emariirates.

In tThe next day we have goingwent with towo cars, because of number of my friends athere were more than 6 persons.ople going.

One day I have spotalkend with my friends to goabout going somewhere as a picnic, so we were planned ton going to Dubai in the uUnited aArab Emariirates.

In tThe next day we havwere going within tow cars, becaus since of number ofmy my friends are more than 6 persons.exceeded 6 people.

One day I haveI spoken with my friends to go somewhere as a picnic, so we werabout going on a picnic. We planned to go Dubai in the uUnited aArab Emariirates.

I understood what you intended here, but I have added some corrections on verb tenses.

In tThe next day, we have going with towneeded to take two cars, because of number of my friends and I are more than 6 personsople.

Check your verb tenses and spelling.

One day I have spokenI made plans with my friends to go somewhere asout and have a picnic, so we wermewhere, so we planned to go Dubai in the uUnited aArab Emariirates.

In the next day we have going withWe would have to use tow cars, because of number of my friends are more than 6 personsmore than 6 people are coming.