There are a number of programs that do this... genuine Fractals (what Resize use) is but one of them.
They are effective but nothing beats a genuinely large original file size.
Just wondering if you can go to something like 5 feet by 7 feet on a photo you take with a mavic 2 pro with a sharp picture? If not, what about a phantom? I guess the next step up would be a inspire?
I have taken the raw image out of the 20 megapixel camera. Processed thru piccure + to clear jens aberrations, processed then thru Topaz Ai up to 6x then downconverted to native image size ( much more focused and detailed) then processed through Topaz AS. Images rival the quality of a 5D S R. Then if desired to upconvert again can achieve the size you want at 300 ppi. Note that this is time consuming but if the image is special one can achieve far beyond what came out of the 20 mp camera.
The maximum size you can print depends on the resolution of your photograph. An example of a resolution would be 4048 × 3032 (in pixels). If you are on a Mac, you can right click on the image in Finder, select GetInfo and you'll find that information there. Here's a link to an article from a company that I've done printing with. It does a good job explaining resolution and print size.
The other issue of increasing the size of your print and maintaining quality can be addressed by a number of programs. The one I currently use is AI Gigapixel from Topaz Labs and have had great results. You find that here.