Trojan.Agent refers to a generic Trojan malware detection. It is used for detections that are either associated with no specific malware families or not enough information is available to pinpoint the malware family.
Trojan.Emotet is commonly spread by email, both using infected attachments as well as by embedded URLs in the email that download this Trojan.
Malwarebytes can remove Trojan.Emotet without further user interaction. However, it is recommended to change all passwords that could have been stolen from the affected system.