Tempo vs. volta
While both tempo and volta can be translated as time in English, they are not interchangeable and describe fundamentally different concepts. Tempo refers to time as a continuous, abstract concept or duration, whereas volta denotes a specific, countable instance or occasion.
Tempo
A1Tempo is used for time as an uncountable, continuous flow. It refers to a duration, a period, the general concept of time, or the weather.
Non ho abbastanza tempo per leggere questo libro.
(I don't have enough time to read this book.)
Il tempo vola quando sei in buona compagnia.
(Time flies when you are in good company.)
Che tempo fa oggi a Milano?
(What is the weather like today in Milan?)
Ci vuole molto tempo per diventare un medico.
(It takes a long time to become a doctor.)
Il primo tempo della partita sta per finire.
(The first half of the match is about to end.)
L'orchestra suonava con un tempo molto veloce.
(The orchestra played with a very fast tempo.)
Volta
A1Volta is used to indicate a specific, countable instance, occasion, or occurrence. It is used when you can count how many times something happens, as in one time or the first time.
Ho visto quel film tre volte.
(I have seen that movie three times.)
C'era una volta un piccolo drago.
(Once upon a time there was a little dragon.)
Questa è la prima volta che vengo a Napoli.
(This is the first time I have come to Naples.)
La prossima volta, cercherò di arrivare in orario.
(Next time, I will try to arrive on time.)
Ogni volta che piove, penso a te.
(Every time it rains, I think of you.)
A volte preferisco stare a casa da solo.
(Sometimes I prefer to stay home alone.)
Summary
In essence, the difference is about countability. Use tempo for the general, uncountable idea of time, its passing, a duration, or the weather. Use volta for a specific, countable occasion or instance. If you can replace the word time with occasion or put a number before it (one time, two times), you should almost certainly use volta.