Update from Laravel 6.20 to newer and Voyager from 1.5.20 to 1.7

[DavidGBz]

Hello, good afternoon.

I have a big problem. I developed long time ago 3 proyects that are still working and been used a lot. They re 3 websites/apps working with LAravel 6.20 and voyager 1.5 the thing is that they all 3 stop working one week ago and I really need to make them to work as my clients are about to kill me.
So, if can somebody give a hand telling me how to update from this versions to a newer one that make it work again without problem will be great.
The website is ok untill I login to the admin panel done with voyager then it keep loading forever.
Any help is welcome, thank you very much.