Oh, manual? Then perhaps your problem is that you need to implement section breaks. Formats aren't supposed to "bleed across" section breaks. You can use the menu to insert a section break at each place where you have a format change. But that might get tedious quickly, so there is another way, maybe.
Have you played with the STYLES menu? You can build a custom style with a set of properties like centered, underlined, bolded, specific font and font size, etc. If you can build three styles, each one according to your descriptions in the 1st post of this thread, then you SHOULD be able to highlight one line, click the special style, highlight the next line, click the next style, then highlight the next line and click the 3rd style. I use that all the time. Should be trivial if tedious.
One of the tricks to create custom styles is to start with your normal style. Then using the styles menu, you can create a new style and "diddle" with its properties. But if all of the "special" styles are based on normal then they are compatible with each other and thus are less problematic.
To take this approach, start with your Word document without any of the special formatting - or even completely blank. Select the "Home" tab on the ribbon. You should see a set of styles in the center and right of the ribbon. To the right of the style list there is a vertical scroll bar and then a button at lower right of the list in a box with a down-pointing triangle. Click this.
You will be able to choose a style (and I suggest whatever is Normal - capitalized because I'm referring to a specific style name). Then you can click from the list of options to "Copy the selected style to create a new style." You will have to name it. But THEN you can RIGHT-click the style to modify it. You have a TON of options for style formatting explicitly including centering or left/right justification, define paragraphs to being with an indent (or even an OUTdent), change font types and weights and sizes, you can even change text color and background.