The following charts shows estimated target heart rate zones for different ages[1].
Aerobic exercise
Here are just a sprinkling of the many aerobic exercises available to you
- Slow, moderate, (low impact, especially if you have any lower torso implants) or fast, dancing,
- Swimming in a pool, doing some type of water aerobics,
- Skiing,
- Biking, some examples of bikes to ride are a vertical, recumbent stationary, and outside biking with a helmet on,
- Walking, in your home, in your apartment, in your yard, and out in the woods if you live nearby any woods, are all good options for walking and hiking, in fact, any place where it is safe to walk would be good choices
- Climbing steps (two at a time for a more vigorous workout),
- Gym membership if you have a gym membership try some of the machines that work your cardiovascular system
It is apparent there are many types of aerobic exercises.
The majority of the following is taken directly from this excellent site, and I do appreciate how well it is written. www.topendsports.com

Use this table to help you set your training intensity based on your heart rate level, using Target Heart Rate (THR). You can get a more accurate figure using actual numbers for resting heart rate and max heart rate and using this Karvonen Calculator.
The following table, which is centered on your current heart rate level (which follows the Karvonen formula[4]) provides some of the information you may need to guide you towards an acceptable heart rate range for your age group. Notice that it goes up in five-year spans, so, once again pick the one closest to your age.
Table of heart rate at training intensities from 50-90%[5]

Related Pages
Determine your own heart rate training ranges using the
Other resources of possible interest
https://www.nia.nih.gov/site-search/YWVyb2JpYyBoZWFydCByYXRlIGd1aWRlbGluZXM%3D
https://www.nia.nih.gov/health/exercise-physical-activity
https://www.nia.nih.gov/site-search/aGVhcnQgcmF0ZSBjaGFydCBmb3IgZXhlcmNpc2U%3D
[1] https://www.topendsports.com/
[2] https://www.topendsports.com/
[3] https://www.topendsports.com/fitness/heartrate-range.htm
[4] The Karvonen formula is your heart rate reserve multiplied by the percentage of intensity plus your resting heart rate. For example, a 50-year-old with a resting heart rate of 65 would calculate as follows: 220 – 50 = 170 for HRmax. 170 – 65 = 105 for RHR.
[5] https://www.topendsports.com/fitness/heartrate-range.htm