Hello,
I always confuse when rather I should use Are or Do , for example :
Do you coming ?
Are you coming
I'll go with Are you coming cuz it sounds better but there are a lot of cases which I don't know what sounds better and I can't follow any rules so I don't know which one is fine.
For example today my client wanted to pay him with Euro .
So I asked him Do you only work with Euro
but I didn't know if I should say instead , Are you only work with Euro.
OK I guess you got my point

Thank you for your help