Past Simple Tense looks like this:

I went out last night.

I met a couple of friends.

We had dinner.

We walked along the river.

We laughed and talked.

We were happy.

We had a good time.

Did you go out last night?

Where did you go?

What did you do last night?

Sometimes past simple tense uses the auxiliary verb “to be” (for example with adjectives) as in “Were they happy?”

Look at this conjugation of the verb “to be” in past simple tense.

I was

You were

He was

It was

She was

We were

You (plural) were

Do not confuse the auxiliary “to be” with the auxiliary”to do” as in this conjugation in the past simple tense:

I did

You did

He did

She did

It did

We did

You (plural) did

They did