I've built a Wireless Access point using hostapd and udhcpd. I have 2 WiFi dongles, one is used as wlan0 other is used as wlan1, I connected one of them to internet and other is keeping working as an Access Point, but no internet. What I want to do is, I'd like to connect wlan0 to wlan1 so that when a request except the website I serve(by nginx at a static ip) comes to device, I want internet connection to happen from the Access Point using the other adaptor. Anybody have an idea how I can do it?
You don't mention anything about the internet connection so unless you edit your question I'll assume that your IP forwarding is working so that clients are about to reach the internet through the access point.
You probably have a few options but I would use DNS to serve the local content and forward requests for other content. You can start with something like this tutorial for setting up