Learn French: Notre génération va changer ce pourcentage. - Our generation is going to change this percentage.

Va changer is the futur proche (near future), formed with the present tense of aller (to go) plus an infinitive. Using it here makes the statement sound very certain, like a strong intention or an inevitable fact. If the speaker used the futur simple (changera), it would sound more like a distant prediction.

Why is it ce pourcentage and not cet or cette pourcentage?

Pourcentage is a masculine noun (most French words ending in -age are masculine). The basic masculine word for 'this' is ce. You only use cet before masculine words that start with a vowel sound. If the word were feminine, you would use cette.

Is notre masculine or feminine in notre génération?

Notre (our) is used for both masculine and feminine singular nouns, so it looks the exact same either way! However, the noun génération is feminine (a helpful tip: most French words ending in -tion are feminine). If it were plural ('our generations'), it would change to nos générations.