you have to use words in context and in sentences to see the different conjugations and meanings. those two words are only similar in some of their letters but they are totally different. so במקביל does mean simultaneously and לקבל does mean to receive, no relation

I see. Thank you for your good explanation !!

It does look like the root of במקביל is קבל, so there is probably a connection. But I don't know it. I tried to search for the etymology of במקביל, but all I found was various definitions (in tandem, alongside, parallel). So I assume that sometime in the history of the Hebrew language, מקביל acquired the meaning "parallel" or "simultaneous" and במקביל became "simultaneously."

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