Learn Spanish (Latin America): Ella sirve la carne con arroz.

The verb for "to serve" is servir. It is a "stem-changing" verb. In the present tense, the e in the stem (serv-) changes to an i (sirv-) for most forms, including él and ella. After changing the stem, you just add the regular -ir verb ending for ella, which is -e, giving you sirve.

Why does meat have "the" (la carne) but rice doesn't (arroz)?

Just like in English, Spanish often drops the article when talking about an unspecified amount of food, especially when it is an accompaniment or side dish like "with rice". It wouldn't be grammatically wrong to say con el arroz, but dropping the article here sounds very natural.

How do I pronounce the "v" in sirve?

In Spanish, the letters v and b make the exact same sound. Because the v in sirve is between vowels, it is pronounced very softly. It sounds like a gentle, lazy English "b" where your lips don't press tightly together.

Could I just say Sirve la carne con arroz without Ella?