5e D&D (upon which the game is based) allows for characters to interchange their actions as long as non-allies don't come between them in initiative.
For example, if you roll a 20 on init, and I roll a 19, and a monster rolls a 17. You could take your bonus action, I could take my action, you could then take your action, followed by me taking my bonus action, then we both move - or any other combination - all before the monster gets to go.
If playing with other players, simply communicate (voice comms?) and work out who does what when (it is frequently in your best interest to go at the same time, such as the second person moving to within melee range so the rogue who technically has the higher initiative can get a sneak attack).
