I upgraded my storage plan and it isnot appearing in my storage

There is no way to increase the storage on your phone. It will always have only the amount of storage it came with. You have probably purchased space on iCloud which is a syncing service to keep apps, photos, etc. in sync across devices. The only way to increase storage on your device is to delete photos, apps, etc that you do not need. Be sure to save important items such as photos to your computer.