The second conditonal is used to talk about impossible situations or unlikely situations.
Second conditional is formed using past simple in the if-clause, and would/could + base form.
Second conditional after I / he/ she /it often use indifferently the subjunctive form were and was (but some people think were is the only form correct).
If we went to South Africa, it’d be the wrong way.
If we stopped at an internet café, we could check out some information.
If he didn’t get the money, he couldn’t buy a ticket.
If she were happy in her school, she wouldn't be looking for another one
The form If I was/were you + I’d + base form is used to give advice.
If I were you, I’d take the car to Bruce Jones.