I am not understand limiting reagent stoichiometry. If I has a big test on this I would get an F-

I've never really been the best when it comes to chemistry. I only started doing it last year and lets just say I got so frustrated I threw my phone at the wall (I have anger issues). I'm not really sure why I'm not understanding it but every time I try to answer the questions I get them wrong. Can someone that is a chemistry genius help me please? I would really appreciate it.