Strava will cover cycling, walking running and you can log any other activities like swimming/weights. For a general "fitness/activity" monitor, e.g. step count then you might want a cheap fitbit etc. I found the fitbit interesting and useful for about 6 months, OK for the next 6 and then I lost it and couldn't care less to replace it.
It is useful to learn how many steps you take in a day just going about your daily routine, e.g. going to office, waling to bus stop, shopping. you soon learn that you can gain X-steps by parking at the end of the car park or walking to the restroom on the far side of the building, plus things like walking to shops vs driving, mowing lawn, doing house work. That can be useful to try to maintain some basic calorie burn, e.g. if you have sat on your bum all day then maybe you get motivated to mow the lawn or go on a short walk.
However,r cone you've learned that its pretty pointless and a very vague measurement of calories burn. I would take the fitbit jogging and of course you use far less steps to cover the same distance and you do it faster using more energy and getting heart rate higher.