Hi Max,
How about using MATLAB's default input dialog (inputdlg)?
Even if you make your own, it's absolutely gonna work the same, and it won't have any advantages.
To find how to use it please refer to matlab documentation.
doc inputdlg
I believe this is enough to solve your prob, if not get back to us.
Good Luck!
Here is an example in the documentation.
![](https://www.mathworks.com/matlabcentral/answers/uploaded_files/175457/image.png)