As you already have a windows laptop or desktop, I would recommend using Reaper as your digital audio workstation also known as DAW
By plugging in your audio interface or mixer to the software, this will allow you to mix the audio files directly in the D a W.
Hope this helps in someway. For more information please visit the link below.
https://reaperaccessibility.com/index.php/Main_Page

I work in the music industry but I don't have much to do with production, I mainly just play. If people are saying reaper then get reaper. What I would say is make sure you get a midi control surface for it. That's not an instrument, that's an actual device with sliders and knobs on it so you can control the track levels and other things with actual physical controls as opposed to a mouse. They come in all shapes and sizes but you can get them fairly cheap especially secondhand. There may be some set up required but it's the only way to mix really. And that goes for everyone, with or without good sight.

You''ll want to take a look at Reaper, and the Reaper accessibility wiki.

The Scarlet 2I2 is a good starting interface. It has to inputs, and it's sold in a kit. Condencer microphone and headphones.

What computer do you have? Mac or Windows?

I use reaper on windows and it’s incredibly accessible

Hey, check out the Los Angeles Braille Institute online. They have remote classes that anyone can join, I think.
They have a class every semester on music production.
Oh, they're free classes too.
https://brailleinstitute.org/losangeles

I know there is the complete control keyboards from native instruments, but I don’t think that’s what you’re looking for. They are fully accessible but I don’t think they would allow you to mix things and stuff.