This is a regular verb. It follows the conjugation pattern of the verb partir.
Present:
A Ana une as pessoas em torno de um objetivo comum.
Ana unites people around a common goal.
Preterite:
O Miguel uniu as duas partes.
Miguel joined the two parts together.
Conditional:
A Clara uniria a equipe novamente.
A Clara uniria a equipa novamente.
Clara would unite the team again.