Active voice is the standard way to speak English. The alternative use is "passive voice". The concept of active voice is that, except for imperative form, sentences in English always have a subject and a verb and express the fact that "somebody/something did something". So, there's always the thought that a specific protagonist has performed a specific action.

The basic structure to think of active voice is:

Subject + Verb + Object

Examples:
I love you
She does not play soccer
They have never been to the USA
It doesn't rain here
The biggest company on the planet sells technology

English verbs can express past, present, or future.
Past: Who did this?
Present: I'm studying 'comparative form'
Future: They will travel to Japan

For each of them, there are three options with most verbs: simple, continuous/progressive (be + -ing), and perfect (have + past participle).

Present simple: I play
Present continuous: I am playing
Present perfect: I have played

Simple forms are used to express actions that happened in the past, everyday actions, and actions that will happen somewhere in the future.

Examples:

Past simple: I watched a movie
Present simple: I watch a movie
Future simple: I will not watch a movie

Continuous/progressive forms (be + -ING) are used when we describe an event as 'in progress' or continuing (at a specific time or up to a specific time).

Past continuous: I was studying
Present continuous: I am not studying
Future continuous: I will be studying

Perfect forms (have + past participle) are used to express a connection between two moments in time, either an earlier and a later past event, a past event and the present, two moments in the future, or that something is/was/will be completed by a particular time.

Past perfect: I had not worked with him yet, and I didn't know him at all
Present perfect: I have seen cases like this before, so I know what to expect
Future perfect: I will have played for 10 years by the end of July

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Perfect continuous forms are possible, too.

Past perfect continuous: I had been watching the show for weeks when it happened
Present perfect continuous: I have been teaching for 15 years
Future perfect continuous: I will have been working for 12 hours