Learn Romanian: Fata se pregătește acum. - The girl is getting ready now.

Se is a reflexive pronoun that literally means "herself". In Romanian, the normal verb a pregăti means "to prepare" (like preparing a meal). When you want to say "getting ready", you are technically preparing yourself, so you use the reflexive form a se pregăti. Literally, this sentence says "The girl prepares herself now."

I learned that "girl" is fată. Why is it spelled fata here?

In Romanian, the word for "the" attaches to the very end of the noun. For feminine nouns that end in -ă like fată, the -ă changes to -a to mean "the". So, fată is "girl", and fata is "the girl".

Could I change the word order and say "Fata pregătește se acum"?

No, in Romanian, the reflexive pronoun (se) almost always comes immediately before the verb. You must keep them together as se pregătește.

Why does pregătește have that -ește ending?

The base verb is a pregăti (to prepare). Many Romanian verbs that end in -i add the special ending -ește for the "he/she/it" forms in the present tense. Since "the girl" is a "she", the verb becomes pregătește.