He makes more money than I do.
Is it alright? Because it doesn't seem alright:) ( I mean, he Makes and I Do-thing)

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Yes, it’s perfect.   “I do” is a shortened form of “I do make” — so the verb “make” is (implicitly) in both halves of the comparative sentence, as is it should be.

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It’s perfect. Note in speech it will be common to hear:
He makes more money than me.
He makes more than me.
He earns more than me.

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Hi.
It is fine.
When comparing things in English, we usually use the proper auxiliary verb the second time to avoid repetition.