It's depend on you.Whenever android version upgrade there may be possibility that older version temp files were still presented in the device. Sometime these files were misbehaving each other instructions so to avoid that you may do factory reset.But...

No

But in airtel site it's show f23 is 5g ready.

It seem that your device have problem, overall device is working fine.

Yes I think this is true because jn airtel site now f23 is 5g ready.