Learn Italian: Incontra il candidato personalmente, che è molto capace. - Meet the candidate personally, as he is very capable.

When an adjective ends in -le or -re (like personale), you drop the final e before adding the -mente suffix. This prevents an awkward pile-up of syllables, which is why it becomes personalmente rather than "personalemente".

Why is incontra translated as a command ("Meet") when it looks like the he/she present tense form?

For regular -are verbs like incontrare, the informal tu imperative (command) form is identical to the third-person singular present tense. If this were a formal command to someone you address with Lei, it would change to incontri.

The translation says "as he is very capable", but doesn't che just mean "who" or "that"?

Literally, yes, it means "who is very capable." However, in Italian, using che after a comma often introduces an explanatory or causal clause. Translating it as "as he is" perfectly captures this natural reasoning tone for English speakers.

How would the adjective capace change if we were talking about multiple candidates?