It has started = active voice, present It was started =active voice, past It started = past tense It is started = passive voice present tense For further explanation - See this link: https://ell.stackexchange.com/questions/41525/difference-between-has-started-and-is-started

Hi Walid, What is the difference? --> I'll give a couple of examples, so you can see the sort of context where we find these 2 structures... It is started -- This is the present simple passive. So, somebody (or something) must do the starting. It is describing what happens in general. e.g. - First the runners all get in position for the race. Then it is started by the coach when he blows his whistle. (The coach does the starting/the race is started by the coach.) - I used to use a key to start my old car, but for my new one, I don't need one! It is started by pressing a button next to the steering wheel. (I do the starting/ the starting is done by me.) It started - - This is the past simple tense (or simple past...). This tense is used to describe the past. It is "active" (not passive). e.g. - We have been in lockdown for 3 months now in my country. It started on 23rd March. - I didn't watch the film on TV last night. It started too late.

Although in everyday speech, you would normally say "it has started". Unless for really specific contexts, it just sounds a little clunky and unnatural.