BE USED TO = you are accustomed to something (it's normal for you). GET USED TO = you are becoming accustomed (the process of adapting). Both are followed by NOUN or -ING form (gerund).
Quick tip: BE USED TO = accustomed (state - it's normal). GET USED TO = becoming accustomed (process - adapting). Both + noun or -ING. Different from USED TO (past habit)!
BE USED TO = Accustomed to (state)
Use BE USED TO when something is normal/familiar for you. You're already accustomed. Followed by noun or -ING form.
I'm used to the weather here. (accustomed to it - it's normal)
She's used to working late. (accustomed to it - normal for her)
We're used to the noise. (accustomed - it doesn't bother us)
They're used to living in a big city. (accustomed - normal)
GET USED TO = Becoming accustomed (process)
Use GET USED TO when you're in the process of becoming accustomed. You're adapting/learning to accept it.
I'm getting used to the new job. (becoming accustomed - in process)
She's getting used to living alone. (adapting to it)
We'll get used to it eventually. (will become accustomed)
It took time to get used to the climate. (process of adapting)
USED TO vs BE/GET USED TO
USED TO + base verb = past habit. BE/GET USED TO + noun/-ING = accustomed to. Different meanings.
I used to smoke. (past habit - I smoked before)
I'm used to smoking. (accustomed to it - it's normal for me)
I'm getting used to smoking. (becoming accustomed - adapting)
Common mistakes
Not "I'm used to smoke." — say "I'm used to smoking.". BE/GET USED TO is followed by noun or -ING form (gerund), not base verb. Used to smoking (not smoke)..
Not "I used to the weather." — say "I'm used to the weather.". USED TO (past habit) + base verb. BE USED TO (accustomed) + noun/-ING. Different structures!.
Practise it
Accustomed (state)? BE USED TO. Becoming accustomed (process)? GET USED TO. Both + noun or -ING. Different from USED TO (past habit)!