An Individual portal account is meant for a person with an individual constituent profile type. A Company portal account is meant for companies, organizations, businesses or groups that have a company constituent profile type.
When registering for a portal account, the top box, Portal Account Type, lets you choose between the Individual or Company profile. It defaults to Individual.
When creating a portal account, the software will validate by name and email address to look for an existing match in the software. If no exact match is found, a new constituent record will be created.
Note that every portal account must have a unique email address. While it is possible to allow companies and individuals to share an email address in the database, they must each have a unique email address if there will be two portal accounts. A constituent identified as the Primary 1 Company Contact will be able to access a company's record from the portal. For more about this, see this article: https://support.donorview.com/en/support/solutions/articles/9000221115-how-does-a-company-or-organization-access-the-donor-portal-