How to pause a instruction

Hi everyone, i'm new on arduino world and i wish to know how do i pause a instruction? e.g. if the user it's going to type a user name and password, how do i stop the instruction to wait the user to provide the information?

I use to program in dev c++ and it has a instruction called "pause" wich stops the program until the next command is given.

thanks in advance for the help

i wish to know how do i pause a instruction?

You can't. Once a machine instruction starts, it is atomic, and will complete one clock tick later.

how do i stop the instruction

How do you stop what instruction?

There are stickies at the top of this forum that you are expected to have read. Clearly you haven't. Come on back after you've read them.

You haven't posted any code, but the usual way to pause is to wait for the user to type something.