Each thermostat normally comes with a wiring diagram. To match one to other you need some extra info.
It would seem Blue = N = Neutral on old and new so that wire is easy enough.
The red - Com is likely the line and I would expect it will go to L
That leaves just the yellow - H wire which is very likely call for heat. It is likely 2 and 3 are the N/O and N/C contacts one is for heating the other for cooling but without more info can't help with which the yellow goes to.
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