You get the W2 from your employer. It will be for the total of everything for the whole year. Just enter the W2 exactly as shown into your return. Box 1 is the total income they paid you. Box 2 will be the total tax withholding they took out for both your pay and bonus.
It is not separated out on your tax return. You enter all your income and pay tax on the total income for the year. Whether you get a refund or owe more tax depends on your total income and how much withholding was taken out and if you qualify for any credits. You have to fill out your 1040 tax return to see how it ends up.
