It appears most people deal with
TheFrugalComputerGuy when it comes to videos. Here is a link to some Calc videos → LibreOffice-Calc. A quick look doesn’t reveal anything specific about your request.
Your request for something specific to Mint Tara is not proper. First, LO runs basically the same whichever OS is being used. As for looks, even within a single OS ( such as Mint Tara) you can modify, through the OS settings, the appearance of most items to your liking. Now multiply the number of options you can set by the number of OS systems available (even just Ubuntu based Linux) and you would have a hard time finding videos looking like yours.
My preference is the LO documentation found here → LO User Guides
Even your request for importing/exporting data is too general as this can mean many things. You may want to look at the Calc getting started guide which contains a section on opening CSV files for a start.