You should have a widget that came with your phone. Long press or an empty page or space (empty page is best since you might need more than one block of space to add one) and you should be able to add a widget somewhere in there for calendar. I use the stock calendar on my X2 and I have this option. It's not the greatest widget, but, it'd do what you are looking for.
If it doesn't do what you are looking for, download some calendar apps, and, check out their widgets until you find what you like. They should all have widgets of multiple sizes( 1 x 1, 2 x 2, etc.) or better, allow you to resize them. Mine only has one size to add, but, once added, if I short press it, I can drag to change the size.
The difference between an app and a widget is that an app is literally an application. A widget is something that gets added to your home screen and offers the functionality of the app it is a widget of. Like I said earlier, I have a calendar app that came with my phone, and, I can add a widget for the calendar app to my home screen. I can view info from the app via the widget, or open the app. I also have a weather app that lets me see the weather, but, I can add a weather widget to get the info without leaving my home screen. Or I can open the actual weather app to see weather info full screen.