A boy becomes Bar Mitzva at age 13 and is then considered a full adult. It is customary to call him up to the Torah as soon as possible after his 13th birthday.
After he had been called up to the Torah and said the final Bracha, his father then makes a Bracha:
Source: Kitzur Shulchan Aruch 61:8
Sunday, 8 Kislev 5775
Please daven for 3 year old נָעֳמִי בַּת דִינָה who is being treated for lymphoma