There is a Word document "kaoshi.docx", please write the corresponding operation steps according to the following operation requirements.

Because I don't have your documents, I can only give you a rough idea. I don't know what your document is like!

The first question:

Center my own text: after selecting the text, click the center button on the paragraph ribbon.

Then click the "Borders and Shading" button in "Paragraph".

Select "Box" in the border and "Text" in "Apply to".

Switch to the Shading tab, select Standard Yellow in Fill, and select Apply to Text.

Question 2: I don't know what yours really looks like, I can only give you a rough idea.

First, select a picture, and then click the Location button on the Arrange ribbon under the Format tab.

Question 3: In the page layout, click the paper size and select A4 from the drop-down list.