I feel like I was born for this question. Okay first there is a ‘selfie ring light’ on amazon that you can buy for around 10 bucks. You slide it on phone. It last for several hours and is rechargeable. Mine came with two for 10$.selfie light amazon link

Then you can get a decent snowball mic that connects to your phone via usb. We actually found one at our local pawn shop for 20$.

Also if you have a decent smart phone. You could just use audio from the smart phone.

it’s easy to add the audio to the video in process.
Depending on Mac or windows computer not sure what to advise you on programs to edit with. If Mac I advise lumafusion (you can edit straight on phone). Hope this helps!