Yes, you can use doctor in a sentence, it just depends on the sentence content
when you use DR. it needs to have a name after such as DR. Davis. doctor is used just describing a doctor such as this sentence- I have to go see my doctor today.
Consult a doctor today
Example sentence - He went to college to become a medical doctor.
The doctor's waiting room was full. I hit the doctor's car.
I was so happy when the Doctor confirmed I was pregnant.
I was nursed by a talented doctor.
The patient sued the doctor for malpractice after suffering complications from a surgical procedure.
You can use the word "want" to express desires or preferences in a sentence. For example: "I want to go to the store."
his attainment was becoming a doctor
When my brother went to the doctor, the doctor said his gum was infected!
I must cancel my doctor's appointment.
i need to address a doctor this second