Present Perfect.
We have done the work.
We’ve bought a new car, so it’s time to sell the old one.
We’ve known each other since school years.
She has wanted to become an actress all her life.
I’ve met him a few times this autumn.
Past Simple.
I played golf in the morning.
The Titanic sank in 1912.
She spoke to him in a low voice.
I woke up, took a shower, got dressed and went out to have breakfast in a café.
When we were friends, he came to me everyday to discuss his ideas.