I have 1/2 electricity in my master bedroom, exterior walls have no power
Turn off the breaker, are all the outlets dead now? Start with the last outlet that was working prior to turning off the breaker pull it out.
If the wires are pushed in to the back of the outlet push in and pull out on each one, if the wire pulls loose that outlet may need to be replaced.
If the wires are pigtailed make sure the wire nuts are tight.then go to the first dead outlet. if no problems are found start at the other end(outlets are normally daisy chained and it will be the last good one or first dead one not passing power to the others. Other than recent construction damaging a wire the above check has fixed many dead outlets.