Some strimmers are auto feed, you tap them on the ground to feed line, "!dont know what it looks like" The line is about 1mm thick usually yellow or green, You might find some push in sections, each side of the spool unit, if so press them in pull the unit out, might have to turn the inside of the unit to get line out, OR if no line, you will have to buy some replacement line, available at all diy places.
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