Once your milk supply is well established and you feel comfortable breast-feeding and confident your baby is doing well, occasional use of a bottle won't interfere with your milk supply.
Babies drink differently from a bottle than from the breast.
Don't let that undermine your success in breast-feeding. When a baby drinks from a bottle, sucking doesn't need to be as vigorous as it does at the breast. Using a bottle could make your baby a bit lazy when returned to your breast. Babies know when they are hungry and when they are full. Then you can offer the bottle again, provided you heed your baby's signals of fullness.