Please see the links and info in my signature for instructional materials for Inkscape. Then you can look things up yourself, in the future. No guarantees you can find the answer you need, but it's always a good place to start. And we're always here if you can't find what you need.
Inkscape, since it's a vector graphic program, works differently than raster graphics programs (like GIMIP). One of the many consequences of this is that the program is set up to draw things 1st and color them afterwards (in raster programs, typically you choose your color 1st). So all you need to do, after you draw what you want with the pencil, is select it ( if it's not already selected), and either click the color you want from the palette, or open the Object Menu > Fill and Stroke dialog > Stroke tab, and from there, it depends on exactly how you want to color the stroke. You can choose the color 1st, but it takes extra clicks, and for most users, it's easier to go with the flow, and draw 1st, color later.
I know, it annoys me to death to have the page border showing by default when you 1st open Inkscape. To remove it, go to File menu > Document Properties > Page tab > uncheck Show page border and Show border shadow. However, you must keep in mind that if your image is not completely inside the page border, it will not completely show up in image viewers or after uploading to internet. So you can periodically replace the page border, to make sure you're still inside the borders. Or on that same page in Document Properties, you'll see a bar with the words "Fit page to selection". After you finish your image, you can select the entire thing, and click that bar/button, and automatically the page border will exactly fit your image, whether you have it showing or not.
OR -- Not only does Inskcape open with the page border showing by default, it opens at 35% zoom. Another way to get the page border more out of the way, is to set the canvas to 100% zoom (which basically means 1 to 1). Now, depending on your screen size and resolution, you'll probably just see one side or another of the page border, and still have plenty of room to draw. But it's entirely up to you, what you're most comfortable with

Please feel free to reply to this message, if you have any further questions. And if you have other problems, just start a new topic. Good luck!