Yes, precisely so. उनको/उन्हें is the respectful form of उसको/उसे. But the meaning is ambiguous, so "वह उनको प्यार करता है" could mean "He loves [them/her/him]".
@Jeevikaa_nan उनसे is also correct. For example let's suppose some guy loves your elder sister or your aunt then you would rather use "उनसे/उनको" instead of "उससे". And since the context is not clear in above sentence, we can use either of them.
Go to settings and seach languages or language input or language settings(either of them as it may be different on your phone) and click on that and choose the languages.^^