I'm doing Psych 3/4 this year and I did Psych 1/2 last year. At the moment, I'm really enjoying Psych because the content is interesting and you can apply what you learn to yourself (which makes a lot of it easier to remember). If your more of a maths/science person I think you will enjoy Psych, especially 3/4 because you learn about the brain and memory.
Although Psych 1/2 isn't necessary for 3/4 I think it is helpful because you learn research methods, which is very important for 3/4.
The workload is pretty high because there is a lot of content that you have to know.
Having decent English skills is beneficial, however, if you work hard it shouldn't be much of a problem, especially because Psych now is more about applying your understanding to scenarios etc.
Hope this helps