Things to take with you
chandlerweb
Spare inner tube(s). Essential when punctured in awful weather.
I use a medium sized "mini" pump with retractable flexible air pipe which connects to the inner tube. As you will read from recent posts, it is best to go for a pretty expensive one.
High security lock and extra cables if you do not have a secure storage area at work. I even cable lock my saddle.
Hi visibility (protective) clothing. Doesn't have to be expensive but I find the more you pay, the better the quality (having said that, Lidl is very popular on this site, and if you're quick there are bargains to get).
I have a bright yellow hi vis jacket with a zipped air vent at the back; bright yellow woollen hat and bright yellow "seal skin" gloves (you may be starting to get the idea....).
I always carry a pair of light nylon overtrousers (black as I couldn't find yellow ones). I also have a pair of seal skin socks which are brilliant. They keep my feet warm and dry as these are virtually waterproof. I wear an old pair of gortex trainers.
I have kept the front and rear lights my bike came with, but also wear a bright LED front light on a head strap, two rear flashing lights, one sewn into the rear of my hat and the other attached to the rear of my pannier.
Others on this forum will give additional advice and, as I have said, it's all here for you to search for.
Conal
P.S.Welcome to the forum!