For the general case, there are five basic conditionals as briefly explained here: https://www.ef.com/wwen/english-resources/english-grammar/conditional/ Also, reported speech changes the verb tenses as briefly explained here: https://www.ef.com/ca/english-resources/english-grammar/tense-changes-when-using-reported-speech/ Now an example: type 1 conditional - real present/future situation Sue: "If I study hard for the next two weeks, I will pass the exam." Reported speech - real present/future situation at a given moment in the past. Sue said that if she studied hard for the following two weeks, she would pass the exam." - - -

I think.you are talking about the 'second conditional', talking about an unreal.situation now. If + past tense would + base verb If I had Soyeon's phone number, I would ask her to dinner. If I earned more money, I would buy a Ferrari. You can replace would with other modals.. In those sentences, could and might work.