1 long workout or 2 shorter workouts?

CASL3

I'm fairly new to exercising and I am trying to primarily lose weight, and I have at least two questions...

I have very consistently been walking for 60+ minutes a day, for about 5 weeks now. This is as fast as I can possibly walk. which ends up around 3.7-3.8 mph. It seems like it is not making my heart pump as hard as it used to, and I dont get out of breath like I used to, even though during this course I am walking up steep inclines pretty often.

Since it doesn't seem to give me the workout I used to get, I've been trying to do some short jogs when I feel myself getting relaxed and my heart slowing down.

My first question is: Am I still burning the same amount of calories even though it doesn't seem nearly as hard as it used to?

#2: My work schedule sometimes does not allow me to walk the full 60 minutes all at once. Is it the same, better, or worse to split it up into two 30 minute walks instead of one 60 minute walk?

Thanks

CASL3

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