How to remove markup when highlighting code in Visual Studio?

Question

Keyboard

I am a beginner programmer, I am writing code in the Visual Studio 2019 program, the problem is that when I try to select text to change in a line, it selects it and starts changing already in the existing code and not before or between it, roughly speaking, for (int i = 0; i < width; i++) I try to add to the brackets (i + 1), respectively, I click on the space in brackets where the space is allocated and when I press the space or writing, it starts to erase where I selected. Is there any setting? Or selection helper

Answer 1

1) Boot from LiveCD.
2) Check the health of the disk
3) If everything is in order with the disk, run the regular system recovery tools. They are on any installation disk.

Answer 2

In general, usually in such cases it is enough to press Insert