It's the dark-blue app with a white "W" on it. The Word home page will open. This option is in the upper-left side of the home page. Skip this step on a Mac. Type in the name of the month for which you want to create your calendar, then press ↵ Enter. Doing so ensures that your month is above your calendar. It's in the blue ribbon at the top of the Word window. The Insert toolbar will open below the ribbon. You'll find this in the "Tables" section of the toolbar. Drag your mouse cursor seven boxes to the right and five (or six, depending on the month) boxes down, then click. This will create a seven-by-five(or seven-by-six) table to serve as your calendar. In the top row of boxes, type in a day of the week for each column. For example, you'd put "Sunday" in the top-left box, "Monday" in the box to the right of that, and so on. Starting with the third horizontal line from the top of the calendar, click and drag the line downward to enlarge the second row of boxes. Repeat this process for each row of boxes until your calendar is the right size for you. Click the box in which the first day of your month starts, type in 1, press Tab ↹, and proceed to number the rest of the days. Once you've numbered the days, you can go back and add events, holidays, appointments, and so on by clicking a day's box, pressing ↵ Enter to start a new line, and typing in the event's name or details. You can add more months to your calendar by clicking below the current month's calendar, pressing ↵ Enter a couple of times, and then repeating the calendar creation process. Press either Ctrl+S (Windows) or ⌘ Command+S (Mac), then select a save location, enter your calendar's name, and click Save.

TL;DR in Vietnamese:
Mở Microsoft Word. Nhấp vào Blank document (Tài liệu trống). Nhập tháng. Nhấp vào thẻ Insert (Chèn). Nhấp chọn Table (Bảng). Tạo bảng. Nhập các thứ trong tuần. Mở rộng ô lịch. Thêm ngày. Thêm thông tin vào lịch. Tạo những tháng khác. Lưu lịch của bạn.