In my view, a successful language learner has to go ahead of the class. Just look up the verb tables for the future tense in your book. You can even find them on the Internet by googling for Italian verbs.
Here is an example I just found by googling.
First-Conjugation Verbs
The future tense (futuro semplice) of first-conjugation regular (-are) verbs is formed first by changing the infinitive ending -are into -er to obtain the root for the future tense. The following future endings are then added to the root: -ò, -ai, -à, -emo, -ete, -anno. (The following table includes a sample conjugation of the verb cantare.)
FUTURE TENSE CONJUGATION OF CANTARE
PERSON SINGULAR PLURAL
I (io) canterò (noi) canteremo
II tu canterai (voi) canterete
III (lui, lei, Lei) canterà (loro, Loro) canteranno
Second- and Third-Conjugation Verbs
The future tense of regular second- and third-conjugation (-ere and -ire) verbs is formed by simply dropping the final -e of the infinitive to obtain the stem and adding to the stem the following future endings: -ò, -ai, -à, -emo, -ete, -anno (the same endings, in fact, as those added to the first-conjugation group). For a sample conjugation, see the table below, which conjugates the verbs credere and partire.
FUTURE TENSE CONJUGATIONS OF CREDERE AND PARTIRE
PERSON SINGULAR PLURAL
I (io) crederò, partirò (noi) crederemo, partiremo
II (tu) crederai, partirai (voi) crederete, partirete
III (lui, lei, Lei) crederà, partirà (loro, Loro) crederanno, partiranno
Future Tense of Irregular Verbs
In the future tense, the verbs dare, stare, and fare simply drop the final -e of their infinitives and form the stems dar-, star- and far-, respectively; the stem of essere is sar-. These stems are then combined with the regular future-tense endings.
The verbs listed below also have an irregularly shortened stem in the future tense (usually, because the vowel a or e is dropped from the infinitive).
IRREGULAR FUTURE TENSE STEMS
INFINITIVE FUTURE STEM
andare andr-
avere avr-
cadere cadr-
dovere dovr-
potere potr-
sapere sapr-
vedere vedr-
vivere vivr-
Then look for the future tense in your reading here at LingQ and save any examples of the future. Save as many as you can.
Later, once you have saved a lot, you can go to the vocabulary page at LingQ and use the Search field to search for *rai or * ranno etc.
I have been searching my vocab list in Russian using search terms like *ей, *ны etc. I find it very useful.