Soft/Hard question on the relation of homology of finite covering spaces and the base (for singular homology, Morse homology and ECH)

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I would like to know how much is to be expected from the relation of the homology of a $n$-sheeted covering manifold $M$ and its base $N$ (let's say $\pi:M\mapsto N, deg \space\pi=n$).

I'm interested in this question at some different layers, first of all, what is the relation of the complexes $C_M$ and $C_N$ (other than sometimes a surjection induced by $\pi$)? Does this map induced by $\pi$ commutes with the respective differentials in $C_M$ and $C_N$? And how much information can we gain at the homology level? (in any sense, information of $N$ known $M$, and viceversa).

Any help is welcome, I'm interested in this question for three specific homologies ranging form less difficult to more difficult: singular homology, Morse homology and Embedded Contact Homology (ECH).