I want to share the internet coming from wifi to the RPi through it's ethernet port to a laptop (in this case a DVR) also the pi should act as a DHCP server. I found one helpful link:
www.diyhobi.com/share-raspberry-pi-wifi-internet-ethernet/
but after completing some steps my entire wifi interface was gone and I have to put pi in the recovery mode. So, I want a solution for this problem.
After fiddling around here and there, I found a simple solution to this problem, after following all the steps from 1 to 5 there is one extra step to be done
sudo dhcpcd
This is a very crucial step to restore all the network interfaces and of your system. Then execute one of the major commands of linux
sudo apt-get update