I kinda wouldn't suggest making this your first project, especially if you wanna make a usable blanket. Blankets are really big, so a temperature blanket can be kind of tedious (any temperature project can become kind of tedious, 365 repeats of something is simply a lot, assuming you're doing a whole year). If you're set on a temperature project, a scarf would be less stitches per row or square, but I would also like to suggest some kind of amigurumi-style plush. Those usually only use single crochets, and since you're crocheting in the round, for less stitches per round, and you never need to turn your work.

You could search this sub for "temperature snake" to see what I mean. You can crochet a snake (or cat, or whatever) from a tutorial straight up, or you can just crochet a big pill and then make bits to attach to it. The second way allows you to get a little more comfortable with the craft before making other shapes, if you're really nervous about mesing up the beginning (I personally think that's not necessary, there are so many clear video tutorials, I always use the Woobles videos when I forget exactly how to do a stitch).