A Candidate may choose one person as a Sponsor.
According to Canon Law (Canon 874), a sponsor must be 16+ years of age, already confirmed and has received the Holy Eucharist, living out a Catholic life, and is not a parent.
It is desirable that a candidate choose as sponsor one who asummed the role of godparent at the candidate's baptism. (Can 893 §2)
(A Proxy may be present on the day of Confirmation should the sponsor be unable to attend due to extenuating circumstances. A parent may stand in as proxy for the sponsor.)