No, in the sentence 'The shoes that he wear...', the verb 'wear' is the first and second person form; the pronoun 'he' is a third person pronoun, requiring the third person verb form 'wears'. 'The shoes that he wears...' is a noun clause, not a complete thought, an incomplete sentence. Examples:
Subject: The shoes that he wears are expensive.
Object: I like the shoes that he wears.
No, it is not grammatically correct to say "a pair of clothes." The correct phrase is "a pair of pants" or "a pair of shoes" because these items come in pairs. "Clothes" is a plural noun.
No.This is singular, is is the singular form of the verb be, a is an indefinite article used before singular nouns, but shoes is plural."This is a black shoe" is correct."These are black shoes" is correct, as well.
"Not like that" can be grammatically correct, depending on the context.
Yes! That is grammatically correct!
Yes, 'for free', is grammatically correct.
The phrase "You are not knowing" is not grammatically correct. Instead, you can use "You do not know" or "You are not aware."
"That was wrong" is a grammatically correct sentence.
Yes, it is grammatically correct.
Yes, Almighty God is grammatically correct.
'What a drunkard you are' is a grammatically correct English sentence.
Yes, "He sailed his boat on the river" is grammatically correct.
The phrase "Is you don't miss me do you" is not grammatically correct. It should be rephrased to something like "Don't you miss me?" to be correct.