Vias, pads and holes are all the same thing. During manufacturing, the board stock is drilled with all the sizes required, then all holes are plated with copper. A non plated hole need to be drilled after plating, or masked before plating.

I think what you want to ask is that with the component seated, how would you get the soldering iron under it to solder the top side? You really do not need to do it. If you don't have plated through holes (PTH), you'll have to route from the bottom excl

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