How much air Earth could retain?

Hi, I'm curious about how much air Earth could retain. It has 1 atm pressure. But what is the maximum atm pressure Earth could retain, related to it's escape velocity? How much air Earth could retain if it was a H/He air, N/O air or CO2 air? Is there a way to calculate this? Could Earth retain an atmosphere of N/O with 100 atm or more for billions of years? As far as I know, Venus has a high atmospheric pressure because of it's heavy air (CO2). If it was like ours, would it be the same?

Could Earth had an atmosphere with 10 atm pressure, assuming it's escape velocity?