Conditional sentences are statements discussing known factors or hypothetical situations and their consequences. Complete conditional sentences contain a conditional clause (often referred to as the if-clause) and the consequence. Consider the following sentences
"I don't care if my brother hit you."
"If I made you mad, I'm sorry."
"If I hit you, I don't remember."
"I don't remember if I hit you or not."
If possible, it would be great to explain why.
if-clauses that are indirect questions (i.e., interrogative content clauses) do not count as parts of conditional sentences. Their function in sentences is completely different.
"I don't remember" can be followed by an indirect question, thus:
I don't remember when George called.
I don't remember where I put my keys.
I don't remember if I hit him.
The same is true of "I don't care".
I don't care how you do it.
I don't care when you come to visit.
I don't care if someone hit you.
For more on indirect questions, see Question about question
The following is a conditional statement, however.
If I made you mad, I'm sorry.
However, it's a weak conditional. It's almost, but not exactly, a use of "if" as "that":
I'm sorry that I made you mad.
"sorry" is unusual in this way.