Camera to App Project Help

Hi, I'm a noob in this stuff and I would like to make a drone with a camera that is controlled on a smartphone with an app i can create (i'm good in programming). The camera feed should be shown on the app.
The problem comes here where I cannot figure out how to send a real-time video stream from the camera to the smartphone. I read on the Internet that since the arduino hasn't much computing power it would be nice to use a raspberry pi along the arduino to manage the camera feed.

Any suggestions?

And ESP32CAM will stream video over WiFi;

I agree that the esp32cam is probably what you are looking for. You can buy them along with a "motherboard" on eBay which has usb which makes programming them easier (search for "esp32cam-mb") or I have recently seen slightly larger esp32cam modules with the usb included.

BTW - I have a sketch here which may also be of interest as it shows some of the things you can easily do with these boards: GitHub - alanesq/esp32cam-demo: esp32cam module demo / shows how you can easily use the esp32cam including reading raw rgb data, streaming, displaying the image etc.(ArduinoIDE or PlatformIO)

Do tha camera and the smartphone need to be on the same wi-fi? or the smartphone connects to the camera wi-fi?
Because I would like to use the drone wherever I want even if there's not wi-fi

Then you could use a mobile phone connected WiFi hot spot, but I am not sure if the ESP32CAM could be connected to via the Internet through one of the Hot spot thingies.

Remember, In a lot of places in the World you cannot fly the drone out of sight .......

Is there a way to use Bluetooth? The hc-12 has a range of 1km and it would be awesome

Bluetooth is short range and the HC-12 is UHF device without the bandwidth for streaming video.

Some tests using a nRF24L01 here;

The esp32cam can connect to an existing wifi or create it's own
see: ESP32 Access Point (AP) for Web Server | Random Nerd Tutorials

BTW - I don't find the onboard antenna on the esp32cam to be as good as other esp32 development boards so it may be worth getting one which is supplied with an external antenna.