Normally ,you can not move apps to SD card on Xiaomi Redmi Note 3.You have to root the phone.It is not wise to install apps on SD card due to performance issue.Even if you want then to move apps to sd card in redmi note for this you need Download FolderMount App from playstore and then Follow below Steps
This app will Mount internal SD card folders to external SD folders.Helps User to Move content from internal to external when a pair is added. Support for Android 2.3 – 6.0. It will also check SDCARD mount status and remount if necessary.
How to Use FolderMount App
Click add to include an organizer pair
Select a source index that you need to move documents from. This ought to be some place in your inside sdcard. Normally situated at/mnt/sdcard
Select a destination catalog that you need to move records to. This ought to be some envelope in your outer sdcard or OTG drive.
FolderMount will offer to move the documents to the destination. Click yes.
After the moving procedure is done, click on the pin. In the event that the pin is green, you’re good to go.
Even if you are Confused then Watch this video