Visual aids: rulers, grid, guides, magnifying glass
Inkscape has a series of "visual aids" to make work easier.
The rulers appear at the top and left and allow us to know the X and Y position where the cursor is at all times and thus be able to know the size of the object that we draw.
The grid allows us to have a base grid on which to align our objects. You can modify the size of the grid in File> Document Properties> Grid.
These are lines that are visible on the computer but are not printed and do not serve to distribute the objects on the sheet and also to align them.
It is a basic instrument in any drawing program. We have magnifying glass + and magnifying glass- and also some default display modes.