Hi nitesh1975,
Welcome to the Apple Community.
Wondering which iOS version is installed on your iPhone.
Try Apple's article "Make a recording in Voice Memos on iPhone:"
NB: (This is for iOS15, or open the article and change to your iOS version at the top for accurate info.)
Eg: says
"Your recording is saved with the name New Recording or the name of your location,
if Location Services is turned on in Settings > Privacy.
To change the name, tap the recording, then tap the name and type a new one".
Complete article: https://support.apple.com/en-au/guide/iphone/iph4d2a39a3b/15.0/ios/15.0
AND
:Share a recording in Voice Memos on iPhone"
says:
In the Voice Memos app , you can share one or more recordings with others
(or send it to your Mac or another device) using AirDrop, Mail, Messages, and more.
Complete article: https://support.apple.com/en-au/guide/iphone/iph3d6dc359/ios
Other articles that may be helpful in becoming familiar with Voice memos.:
Duplicate a recording in Voice Memos on iPhone (useful when editing / making changes)
https://support.apple.com/en-au/guide/iphone/iphbda915db2/ios
Edit or delete a recording in Voice Memos on iPhone
https://support.apple.com/en-au/guide/iphone/iphc9bdaee83/ios
Organize recordings in Voice Memos on iPhone
https://support.apple.com/en-au/guide/iphone/iph73bfaba07/ios
All the best :-)