Juanito Maravilla

Juan Gómez, better known as Juanito, was a very famous Spanish soccer player during the late 70's and 80's. Born in Málaga, in the south of Spain, he soon went to Madrid to join Atlético, one of the best Spanish squads. When he was playing his very first match with the professionals, he broke his leg, which prevented him from playing for a very long time. Due to this, his club decided to not have/keep him any longer. When he got over his injury, he joined a second division squad, Burgos, where he played for four years and got promoted to the first division. In Burgos he was the best player and many clubs wanted to have him, but he chose Real Madrid. He played for Real Madrid for ten years and there he became a legend. Though he had everything: having played in the best Spanish club, having fans that adored him and having won many trophies, he had one/a huge problem: his volcanic character. He was sent off the ground a couple of times playing the former Champion's League and was sanctioned, though not very severely. However, once in Munich, he was sent off the ground and got a five year sanction (he was not allowed to play European championships for that time). After this happened, he came back to Málaga and played there, again getting promoted to the first division before he stopped playing football a couple of years afterwards. He then became a coach and began to work for a club called Mérida. He wanted to be Real Madrid's coach some day, but one night on his way back from Madrid after watching a game, he had a car accident and passed away at the age of 37. His passing was a shock/was extremely jarring for Spanish football, especially for Real Madrid players and fans, who loved him very much.

This was really good.  Most corrections were for commas, which are tough and inconsistently used by even the most literate of English speakers, and for sounding more natural.

Keep it up!

P.S.  For the sentence with, "In Burgos he was the best," it would be more grammatically correct to say, "Though in Burgos he was...," OR end the sentence after, "have him," and make the end of the sentence it's own sentence.

Ejemplo: "That being said, he still chose Real Madrid."

Juan Gómez, better known as Juanito, was a <strike>very</strike> famous Spanish footballer <strike>during</strike> from the late 70s <strike>and</strike> to 80s. He was born in Málaga, Southern Spain, but he <strike>soon</strike> <strike>went</strike> moved to Madrid to join Atlético Football Club, one of the best Spanish football squads.
When he was playing his <strike>very</strike> first match with the professionals, he broke his leg. <strike>which</strike> This prevented him from playing for a <strike>very</strike> long time. Due to this, his club decided not to have him any longer. When he got over his <strike>injure</strike> injury, he joined Burgos — a second division squad — where he played for four years and got promoted to <strike>the</strike> first division.
 In Burgos, he was the best player <strike>and</strike> so many clubs wanted to have him but he chose Real Madrid. He played for Real Madrid for ten years. <strike>and</strike> There he became a legend.
He (had) got everything: he played in the best Spanish club; the fans adored him, and he won many trophies. But he had a huge serious problem: his volcanic character. He was sent off the ground pitch a couple of several times (playing the former Champions League) <strike style="background-color: rgb(255, 255, 0);">and</strike> but he was sanctioned not very severely. However, <strike>once</strike> when (he was) in Munich, he was sent off the ground pitch and <strike>got</strike> given a five year sanction (he was not allowed to play European championships for that time). After this (happened), he came back to Málaga and played  there. When he <strike>getting</strike> was promoted to the first division again, <strike>and</strike> he stopped playing football a couple of years. Afterwards, <strike>Then</strike> he became a coach and began to work for a club called Mérida. He wanted to be Real Madrid's coach some day. <strike>but</strike> One night, on his way back from Madrid after watching a game, he had a car accident and passed away at the age of 37. His passing was a commotion for Spanish football, especially for Real Madrid players and fans, who loved him <strike>very</strike> so much.