Welcome
Also would help if we had a bit more information.
As mentioned already there could be a loose connection somewhere etc or the receptacles (outlets) where only one port (plug-in) works could be switched. These "outlets" that you are referring to are actually called "duplex receptacles".
First, did this just start? Have the receptacles (plug-ins) worked in the recent past? What room of the house are these in? Have you lived at this home for a while and they have been working and suddenly stopped? Are you in the US or Canada?
Try to give us some information so we can get a better idea of what it may be before you start taking receptacles out of the wall and inspecting them.
Most times if only one of the two (ports) have power on a receptacle it is very possible that these receptacles are controlled by a light switch. Things such as floor lamps are plugged in so when you enter a room and flip the switch on the wall the lamp goes on keeping you from having to walk thru a dark room to turn the lamp on.
Can't assume too soon how these three are wired. When you look at them from left to middle to right does not necessarily mean that is how they are physically wired behind the wall surface material and also we can't at this time determine if these are even on the same circuit.
Do you know if any circuit breakers are tripped? Do you know how to check to see if any are tripped. Do you know what a GFCI receptacle looks like? Have you checked to see if all GFCI receptacles are functioning; we don't know what room these receptacles are in so there is too much guess work on our end.
Give us a bit of an idea of your skill level with residential electrical so we have an idea of where our suggestion/advice list should start.
