In This month, I was buy bought many a lot of clothes, It including four T-shirts, one coat, three pairs of khaki paints pants, two pairs of sneakers and five pairs of socks. The T-shirts I bought are white, black and brown. The coat I bought are is black. The khaki paints pants I bought are white, grey and black. The sneakers I bought are white and black. The pairs of socks are white and black. It has been a year since I last bought new clothes.
Please see my corrections above. Also, note the following:
1. "was buy" is wrong in any context. You needed the past simple.
2. Use "many" with countable nouns. "Clothes" is uncountable so you can use only "a lot of" there.
3. You must capitalise the word "I" (first person singular pronoun)
every time you write it.
4. Take care with your spelling - you misspelled "pants" twice.
5. There was no need to write a new sentence about the colour of the various pieces of clothing and you didn't need to keep repeating "I bought". I left them in so that you could see how many times you failed to capitalise "I". A much neater version would be "The T-shirts are white, black and brown, the coat is black, the pants are white, grey and black, and the sneakers and socks are black and white".
