The indirect question always occurs in a dependent clause and never has question word order, i.e., never reverses the subject and verb. The indirect question takes a period.
...I want to know where you were.
Direct question would be "Where were you?"
...I am asking about how long it took.
Direct question would be "How long did it take?"
...My question is what time you left.
Direct question would be "What time did you leave?"
Happy punctuating!
Margie