If you're using Samsung "a" series so this series doesn't have call recording feature !!! For that you will have to install True Caller by this you can't only record calls but also find the identity of unknown callers !!!
Your region (Pakistan) has laws and regulations that forbid call recording. Due to that reason you may not see the Call Recording option in Phone. Samsung will add the feature as soon as your region allows for it.
The A series has the Call Recorder, but its only your region that does not allow it.
Please only take answers from a trusted Member.
In the meanwhile you can Download an app from the Galaxy Store. Make sure you trust the app. If you want I can provide you with one.
Hope it helped. Please mark this comment as a solution, it would help a lot.
