Ensure you have part1.rar and any other numbered parts in the sequence. You cannot extract Part 2 by itself.
Right-click P30pl3H4t3W3dd1ngHDR.yamil.part1.rar . P30pl3H4t3W3dd1ngHDR.yamil.part2.rar
Choose "Extract Here" or "Extract to [Folder Name]" . Ensure you have part1