How do I transfer videos from my laptop to my iPhone?

My sister s wedding was yesterday and I took all pictures and videos on my Sony DSC-WX350 camera. I transferred the pictures from my camera to my phone but it wouldn t let me transfer the videos. I learned that I could only transfer MP4 videos and I didn't record with that format. I was able to transfer the videos from my camera to my laptop. I also changed the format to MP4 using PlayMemories. I also saved them. My Wi-Fi has been acting up for 3 days now. It works for a few seconds and it stops working for a few seconds. So I connected my phone and laptop via Bluetooth. I'm using FileTaskManager. The problem is that whenever I select a video and try sending it to my phone, the window closes. When I open it again, and I go on history, it says it failed to send. I also can't seem to figure out a way to transfer the MP4 videos to my camera. I would ve downloaded ITunes but like I said, my Wi-Fi isn't working. I tried transferring pictures from my laptop to my phone too but it still fails to work. I've been trying to figure this out all day. My laptop is Windows 7 Professional.

I wouldn't suggest using bluetooth to do this to begin with. Depending on the quality/size of the video files it would take very long.

You could
-connect the phone through a USB cable & sync them through iTunes
-upload them to Google Photos/Flickr or similar sites & download/access them through their respective apps on the iPhone.

You should be able to transfer them using a wired connection, such as a USB cable. The cable that you use to charge your phone, can be unplugged from the charger and connected to your laptop instead. When connected to the laptop, not only will the laptop charge the phone, it can also transfer files between the devices.

First, you will not be able to transfer the MP4 files to your camera. Cameras rarely allow import of anything and certainly would never accept a format, MP4, that it doesn't use.

Second: transferring files using bluetooth. Make sure you have set up the network properly. Maybe this link will help.
https://www.howtogeek.com/214185/beginner-geek-how-to-pair-devices-over-bluetooth/

Connect the phone using a USB cable. Make sure that any single file does NOT break the limit of 4gb in size, and also that there's enough room for it. Also the SHAPE of the media is important. You should take a movie with you device and copy it to a pc. You should then examine its shape etc.Eg start VLCplayer, pause the movie, choose media information and check the CODEC tab. You will need to make any movies you create match these settings.Alternatively you may be able to install an app that will play them.

Use Finder?