Do you mean feel your babies movement or hear babies heartbeat? You can't ever feel the heartbeat, but you can usually hear it around 8 weeks, if you have an internal ultrasound done. Otherwise 10-12 weeks or so, at your doctors appointment, you should be able to hear it with the doppler.
You can usually feel your babies movements around week 16, but could be as late as week 26- depending on the pregnancy.
You can't "feel" your baby's heartbeat.