Should I enter an amount in Box 2a since it's blank on 1099-R and the box under 2a "Total distribution" is checked and the distribution code is "G"-Direct rollover?

Is the amount in Box 1 totally taxable since Box 2a is blank but the box under 2a is checked Total distribution. It is a direct rollover into an IRA and I thought a direct rollover wasn't taxable until distributions start for that IRA. Turbo Tax keeps asking me if I'm sure my entries are correct for that section.