.NET MAUI is the application user interface framework that now comes with .NET (Since .NET 6)
.NET is the overarching term for everything .NET.
.NET Framework refers to every version of .NET 4.8 and before. .NET Framework only ran on Windows (unless you used Xamarin to run it on other frameworks. Xamarin was a third party implementation of the .NET framework, it is now owned by Microsoft as well).
.NET Core is the new version of .NET. In the first 4 (I think) versions it had it's own branding, .NET core 1, 2, 2.1, and 3. .NET Core runs cross platform across the desktop OS's natively. Xamarin was still used for mobile development.
What would have been .NET Core 4 has been rebranded as .NET 5. Xamarin at this time was brought into the fold, allowing full functionality of .NET Core API's across desktop and mobile. I believe this rebranding was done because .NET Core was being considered full feature enough to take over the legacy of .NET.
One thing you didn't mention but I'll touch on as well, is .NET Standard. Lot's of people get confused about .NET Standard. .NET Standard is just the definition of what different frameworks that implement .NET Standard can use. So if you write your code to target .NET Standard you can't use .NET Core specific API's but what you can do is have the same code compiled against .NET Standard referenced in your .NET 4.5 - 4.8 Code, or your Unity Code, or your Xamarin code. It was primarily designed with libraries in mind.
ASP.NET Is the web framework that comes with .NET
.NET MAUI is the application user interface framework that now comes with .NET (Since .NET 6)
.NET is the overarching term for everything .NET.
.NET Framework refers to every version of .NET 4.8 and before. .NET Framework only ran on Windows (unless you used Xamarin to run it on other frameworks. Xamarin was a third party implementation of the .NET framework, it is now owned by Microsoft as well).
.NET Core is the new version of .NET. In the first 4 (I think) versions it had it's own branding, .NET core 1, 2, 2.1, and 3. .NET Core runs cross platform across the desktop OS's natively. Xamarin was still used for mobile development.
What would have been .NET Core 4 has been rebranded as .NET 5. Xamarin at this time was brought into the fold, allowing full functionality of .NET Core API's across desktop and mobile. I believe this rebranding was done because .NET Core was being considered full feature enough to take over the legacy of .NET.
One thing you didn't mention but I'll touch on as well, is .NET Standard. Lot's of people get confused about .NET Standard. .NET Standard is just the definition of what different frameworks that implement .NET Standard can use. So if you write your code to target .NET Standard you can't use .NET Core specific API's but what you can do is have the same code compiled against .NET Standard referenced in your .NET 4.5 - 4.8 Code, or your Unity Code, or your Xamarin code. It was primarily designed with libraries in mind.