Students often use the word “should” incorrectly. “Should” is not a replacement for “have to.”
Here is how should is used: You shouldn’t swear in church. You shouldn’t take someone’s food without asking. You should have apologized to him for eating his lunch.
Occasionally should is used to mean very likely, for example: “According to the weather forecast, it should rain tomorrow.”
Here’s an example of how a conversation between two Americans might sound:
“We should get together this weekend.”
“Yeah. How should I get to your house?”
“Take the highway to exit 45. Go north on 34 for about eight miles. Then turn right onto Beaver Road. You should be able to see my house from the road, it’s the bright pink house on the hill.”
“Do I have to take the highway? There’s construction.”
“Well it’s the easiest way to cross the river, otherwise you’d have to use the other bridge and drive a lot farther.”
Notice the directions were not worded “You should take the highway… You should go north…”
It’s always easy to replace “should” with something else, so if you don’t want to you don’t have to use it.