Used can also be used as an adjective meaning ‘accustomed/habituated’. It is then followed or preceded by be, become or get in any tense and followed by the preposition to + noun/pronoun or gerund:
I am used to do it.
I am used to staying in the noisy room.
You will be used to living here.
She will get used to doing such type of job.
They will soon get used to come to the office in time.
I got used to driving in the busy road soon.
Here in the sentence ‘I am used to staying in the noisy room.’ refers that I don’t get any problem staying in the noisy room.
I am used to has the meaning I don’t mind / I don’t feel trouble / It doesn’t give any disturbance to me.
USED is the past tense of a defective verb which has no present tense.
Affirmative: used not / usedn’t for all persons
Interrogative: used you/he/they? etc.
Negative interrogative: used you not/usedn’t you?
Negative interrogative can also be with did:
Didn’t I use to go there?
Did he use to come?
Didn’t he use to come?
Sometimes used is used to refer to the habitual fact in the past tense:
Remember USED has no present form.
I used to bathe in this river.
Once, I used to dislike her but now I like her.
He used to kiss his wife when he went to the office.
I used to help him in my student life.