A low-code development platform provides a development environment used to create application software through a graphical user interface instead of traditional hand-coded computer programming.
A low-coded platform may produce entirely operational applications, or require additional coding for specific situations. - Wiki
Low-code development is a new approach in which the software is not developed from scratch. In this approach, you can take up the existing solution and then develop the additional component which is required. This approach helps you to build up the customized solution with the existing information rather than developing it from scratch.
It provides better customization as you have control over the code on the changes which you want to make. Some tools may or may not completely provide control of the code. It depends on the vendor which you are using.
In terms of code, everything is built from scratch, However in terms of low-code you don't need to build the base, You can start coding on an already available base to save time.
It helps you provide better control over the code by providing flexibility to make changes according to your requirements.