given the OP is a noob, a noob should not be running the course the day of. probably not even the day before. not if they want legs when the race starts. they should warm up, of course, but we should not assume they are trained up like a college cross runner, where a couple miles for warmup might be a drop in the bucket.
as one poster noted, race day is often fairly busy. you drive to the place. park. walk to the packet pickup. get that. walk to the place to get dressed and leave your stuff. do that. walk to a spot and do some warmup. then walk to the line and wait for the race. then race, etc. it can be a little draining. so to me the last thing a noob needs is go run the course the day before. the people advising it are probably the sorts who run 5-10 miles a day.
hence why i said, do it about a week or week and a half early (or even earlier than that) or don't bother. scouting is fine but at that fitness level you want to have gas in the tank and be recovered for race day. if the race is this weekend and it's wednesday that's cutting it close, and i'd stick to my normal training. which might be similar distance but less of, run a block, wait for a light, run another, wait for it, etc. it's different running a street course in normal daytime without the cross streets blocked, tape/barriers up, etc.
if you've cut it too close you can get in your car and drive the route. it's not exactly the same as running or walking it but you can get the basic drift at lower energy expense. ok, start here. turn left there. etc.
i also agree with the other poster that a noob is most likely just following the pack and not in inch-saving mode. to me knowing the course well is more of a front of pack concern. like i did a NYRR thing and just signed up. no clue if it was a circle, up and back, or point to point. no watch, lost sense of how long i'd gone, up with the leaders to halfway, faded to top 10 or 15. yeah, that situation, you want to know, out and back, and halfway is x, because there is no one to follow and you may have to figure out your own path and pacing like it's a school meet.