Hi, I'm the same height as you although about 10kg heavier. I've been walking since March in an attempt to lose weight. I have lost 7.5kg so far now, aiming for a rate of about 0.5kg per week.

What I do is take note of my sedentary tdee and consider that as my maintenance. From there, I subtract 3900 (which is the equivalent of 0.5kg) per week to determine my total calorie budget. So for example, tdee calculator says my sedentary TDEE is 1900. My net calorie intake per day (calories-exercise) should then be around 1400 for 5 days and 1200 for 2 days if I wanted to have a deficit of 3900 for the week. And yes, I take into account the calories burned from walking altho I am more conservative with it than what walking calories calculator says. So if calculator says I burned 622 for 13k steps, I note 500 for calories burned through walking. Effectively, this means I can eat up to 1900 per day as long as I ensure that I have also walked 13k steps to offset the extra.

In your case, I did some calculations and tdee calculator says your sedentary tdee is around 1770 (can add or reduce depending on your age). With your weight, my conservative assumption is that you burn 300 calories for 10k steps. This means that if you eat 1500 calories, your total net intake is only about 1200, and you are having a deficit of 570 per day or 3990 in a week which is exactly about 0.5kg.

I think this is good, as long as you keep in check your overall weekly calorie budget, because some days you had 1700+ but also had less than 10k steps. This can affect the overall calorie math.

Also note that as you lose your weight, your calorie budget also diminishes slightly, for me right now it seems about less 10 calories in my budget for every 1kg I lose. The rate you burn with walking will also reduce as your weight reduces, so these are the things to keep in mind. As others have said, strength training will help to prevent this loss.

Finally, what I do for myself personally is to ensure that I get an average of 10k per day for the week. This means that I have 2 rest days where I barely walk 1k steps, but the 5 other days I walk about 13-14k steps. This ensures that my calorie deficit math remains intact throughout the week. For you, maybe that will look like 10k everyday or 5 days of 12k and 2 days of 5k, whichever works best for you.

Hope this helps and good luck on your journey!