how do I get my documents certified

Please house, I want to send my documents for an MSc application abroad and am supposed to send certified documents. please what are certified documents and who do I meet to certify my documents? I am currently resident in kaduna. thanks for your prompt reply

MAKE PHOTOCOPIES OF ALL YOUR ORIGINAL CREDENTIALS & TAKE THEM + ORIGINALS TO FEDERAL HIGH COURT, THERE THEY WILL STAMP CERTIFIED TRUE COPY ON IT + SIGNATURE.

PS: NO BE FREE OOOOH
CHEERS.