Learn Hardcore Russian: Я отреставрирую старую картину.

Отреставрирую is the first person singular form of a perfective verb. Because perfective verbs in Russian have no present tense, their forms are used to indicate future actions that will be completed. So even though it ends in -ю (which might also be seen in present-tense forms), here it means "I will restore."

Why does the verb form look like it might be present-tense but is translated as a future action?

The appearance of the -ю ending can be misleading, as it is common in present-tense conjugations. However, because отреставрирую comes from a perfective verb, it cannot express an ongoing present action—instead, it indicates that the action will occur in the future and will be completed once done.

What effect does the prefix от- have in отреставрирую, and is this meaningfully different from using the base form without it?

The prefix от- added to реставрировать helps form a perfective verb that emphasizes the completion or the end result of the restoration process. While both реставрирую and отреставрирую might be understood in conversation, the version with от- often implies that the restoration is to be carried out thoroughly and completely—a nuance that can be especially appropriate when referring to the careful work of restoring an old painting.

How does the subject pronoun Я function in this sentence?