mov to mp4 issue

The issue isn't the .MOV format. The issue you're having is working with media from a phone. The variables you have are:

1. It's recording HEVC, which is a terrible video codec for editing. It's extremely compressed and requires advanced algorithms to decompress, which makes it very difficult to play in real-time. (Learning about video codecs.)

2. Phones record Variable Framerate, which is like poison to editing software that likes a constant framerate. That combined with the HEVC will result in basically unplayable footage. This needs to be corrected. (Learning about VFR.)

3. Unless you turn it off, phones record in HDR, which is still a relatively niche color space to be working in. This is ok when you are staying in the Apple ecosystem, but if you want to actually work with, color grade, and deliver HDR outside of that then you'll need special equipment to monitor it properly. I recommend disabling that on the phone unless your intention is to work in the HDR niche. 99.9% of media is still going to be consumed as Rec709.

So it seems like you've been dealing with addressing pieces of these phone-related issues, but you're not also getting the color space conversion from HDR to Rec709 correct in the process. You should be able to use a program like Shutter Encoder to do each of these things in one transcode. You can keep all the settings for the video the same (frame size, framerate, etc.) but transcode to an edit-friendly format like Quicktime ProRes 422 LT (also in an .MOV container, but again the container isn't the issue, the codec is. MOV can hold one of the best editing codecs - ProRes - or one of the worst: H265/HEVC). In Shutter Encoder there is also options to override the color space in the Colorimetry menu so you can do a proper conversion from HDR to Rec709 during the transcode. Setting the Colorspace option to Rec.709 should do the trick.

This should hopefully be all the info you need to both understand the issue(s) you're facing and how to address them. Turn off High Efficiency Mode on the phone's video/photo recording settings and I think that will disable the HDR, but you'll still likely get the HEVC/VFR issues, as most phones do. But the HDR is just adding the extra complication for you here, otherwise Handbrake would have done the trick.

Please use the free MediaInfo and post a screenshot of the properties of your media in tree view:
https://mediaarea.net/en/MediaInfo

https://community.adobe.com/t5/premiere-pro-discussions/iphone-12-pro-max-and-13-pro-hdr-footage-blown-out-in-premiere-pro-2022-v22-0/m-p/12488904

I am so done. I've LITTERALY been trying to convert this file to mp4 for a month now and I cannot find any solutions.

By @Maxime242404783yif

Where does the file come from? Camera, smartphone, internet download, or?

One app that i have had success with when other encoders fail is TMPGEnc Video Mastering Works 7 that seems to eat everything. It does cost money but the trial version will work and will not leave any watermarks in the output.

Or, try the freeware Shutter Encoder to either rewrap the file to se if it works or output it to let´s say Apple ProRes. Shutter Encoder is based on ffmpeg but may use better command than you did. It´s worth trying.