Today, so many countries have learned to love fast food ¶
. Actually, even in just Britain, there isare 42.,000 fast food restaurants ¶
. There isare so many tiypes of fast food Iin Brazil like Mc dDonalds, Burguer King, Subway, and Habibs.

"Actually, just Britain" makes it sound like you're contradicting the previous statement and saying it's just Britain that loves fast food

In English speaking countries, "," is the thousands seperator and "." is the decimal seperator.

"is" is singular, "are" is plural

The greatest is Mc donalds in Brazil, or maybe in the world, is McDonalds but Subway has the most restaurants ¶
. My family eat fast food one or two times per week.

The kids love it. ¶
¶
This way of eating started in the USA, in the 1950" ¶
s. The rise of fast food begian after the second world war. ¶
Some companies like Mc dDonalds, KFC and others were sucecessfull to in sell hamburgers, fries, chicken, milkshake ¶
s, etc., so many people believe that siymbolises the aAmerican dream. ¶
The aAmerican dream that meanis the idea that anyone in the united state can achieve success thougth work hard and determination.

This show the power of the USA's economy since or after the Second world war.

"since" and "after" mean the same here, so you wouldn't use "or" here

The fast food culture was not limited to the USA, but spread inthroughout the world

Today, so many countries learned to love fast food ¶
Actually¶
in just Britain, there is 42.000 fast food restaurants .¶
There isare so many tiypes of fast food In Brazil like Mc dDonald's, Burguer King, Subway, Habibs.

There is one type
there are many types

is is for singular, are is for plural

The greatest isIn Brazil Mc donald's in Brazil maybes the best, and maybe it is also the best in the world, but Subway has the most restaurants ¶
My family eats fast food one or two times per week.

The kids love it ¶
¶
¶
This way of eating started in USA, in the 1950" 's¶
The rise of fast food begian after second world war ¶
Some companies like Mc dDonald's, KFC and other weres sucecessfull to selly sold hamburger,s fries, chicken, and milkshake s¶
so many people believe that siymbolizese the american dream ¶
The american dream that meanrepresents the idea that anyone in the uUnited sStates can achieve success througth work hardhard work and determination.

When making a list you put a comma with the last element as well. You can search for the oxford comma rule to learn more about this.

This show's the power of USA's economy since or after the Second world war.

Today, so many countries have learned to love fast food ¶
Actually just.¶
Just in Britain, there isare over 42.000 fast food restaurants .¶
There isare so many tiypes of fast food Iplaces in Brazil like Mc dDonald's, Burguer King, Subway, and Habib's.

The greatestmost popular one is Mc dDonald's in Brazil and maybe in the world, but Subway has the most restaurants .¶
My family eats fast food once or two timesice per week.

The kids love it ¶
! ¶
¶
This way of eating started in USA, in the 1950" 's. ¶
The rise of fast food begian after sthe Second wWorld wWar ¶
Some c. ¶
Companies like Mc dDonald's, KFC and other were succesfull to in selling hamburgers, fries, [fried] chicken, and milkshake ¶
so ms. ¶
Many people believe that sithey symbolise the aAmerican dDream. ¶
The a"American dDream that mean" is the idea that anyone in the uUnited sStates can achieve success througth work hardhard work and determination.

This showcases the power of USA economy since or after the Second wWorld wWar.

The fFast food culture was not [just] limited to USA, bu. It spread in thed to the entire world.