How can English distinguish ing form, third person singular form, ongoing tense and past tense? The exam is coming. I haven't differentiated them yet.

How can English distinguish ing form, third person singular form, ongoing tense and past tense? The exam is coming. I haven't differentiated them yet.

I'm walking. I'm walking. I'm walking. I'm walking. I'm walking. I'm walking
He likes it. / he does his home all by himself
I went to Shanghai yesterday
To distinguish, just find out when the action happened