Anna:

my brother's name is jake.
He is 7 years old.
His favorite fruit is apple.
He has many LEGO blocks.

correct:

My brother's name is Jake.
He is 7 years old.
His favorite fruit is apple.
He has many Lego blocks.

Explanation:

When writing a sentence you should begin with a capital letter and ends with a period.

When writing a name it is always written in a capital letter.

Note:

Be careful how to write common and proper noun.

Proper noun- a word or group of words that is the name of person or place and always begins with a capital letter.

example: London, Sara, South Korea, Science, Math.

Common noun- a noun that is the name of a group of similar things,

example: book, subject, television, park, school.

 Hi Anna,

     Thank you for submitting your assignment about your brother Jake. Take time to study the corrections and keep practicing how to write a sentence. Job well done!