Too many people ghet caught up in the word "trackday". As soon as you mention its a racetrack, they think there is some kind of expectation of performance. Not so.
At our last trackday, just in the beginner group alone, there was a massive amount of variance in experience levels and skillsets. So what? As long as you're learning and having fun, it's a success. Some people remain in the beginner group all yr, some move up after a day or two. My first trackday at the rider's meeting, passing rules were explained, and I wanted to work on passing......so I started in the intermediate group, and began racing a week later.
Also, at our last trackday, I saw a bunch of less than suitable riding gear. Don't come without full leathers, a back protector, full face helmet, riding boots and gauntlet gloves. As far as I am concerned, riders should always wear what they'd want to crash in, regardless of where they are, however, that's another discussion altogether........but at least at the track we can control what we allow riders to wear.
Even if you are riding a streetbike at a trackday, I would do my best to remove as many expensive items as possible to avoid huge costs, should things go sideways. Remove fairings, lights, mirrors etc.....>All that stuff is expensive to replace, and unneccessary for a learning trackday rider. Or buy a set of unpainted race fairings....they are $600, and that's cheaper than one OEM panel will cost from a dealer, should you crash on your shiny street plastic.
If you do a trackday or two, and decide that you love it and you want to continue. I suggest getting a dedicated trackbike. It is cheaper in the long run, and you can buy a track prepped beater for a couple grand, ready to ride.