a — used to say or suggest that something is the proper, reasonable, or best thing to do.

What do you mean by should?

1. modal verb. You use should when you are saying what would be the right thing to do or the right state for something to be in.

Should is used for?

The main use of should now is to tell somebody what they ought to do, to give advice, or to add emphasis: We should really go and visit them soon. You should have seen it!