"You are used to" vs. "you used to use"
Solution 1:
In the first sentence, If you are used to means 'If you are familiar with'. In the second, If you used to use means 'If you were in the habit of using in the past'.
Solution 2:
Used to + verb means explaining something about the past:
I used to go to the gym, but now I've no time to do it.
Be used to + noun means explaining something that you are familiar with:
I am used to loud music because I was in a rock band.
I am used to working till late.