Select the point where you want to insert an instruction and click [Insert Instruction (I)] on the [Logic (L)] menu.
To delete, on the [Edit (E)] menu, click [Delete (D)].
With Online Editing, you cannot create a new variable. Allocate existing variables when adding instructions.
You cannot create new Function Blocks, place them from a package, or edit programs within Function Blocks.
Alternatively, you can insert/delete instructions from the [Edit (E)] menu or right-click the instruction.