Hello and welcome - you have come to the right place for information and support. It's such a shock at first, isn't it, but you'll find you soon adjust to a different lifestyle?
I suggest you start with the Learning Zone - orange tab above - and slowly work your way through for Type 2. I did one module a day, so I could take everything in, and of course you can always re-visit.
To tailor our suggestions, you really need to find out what your HbA1c was and post it (mine is in my signature below this post). Anything 48 and above is diabetic and the higher the number, the more care you need to take. If it is only just above, a few simple lifestyle tweaks may be all you need.
Your were rightly advised to reduce your carb intake. This includes bread, rice, pasta, potatoes, cereals, processed foods, many fruits. The suggested level is below 130gm a day. However everyone is different and what is right for one, is not right for another. Some people are very sensitive to carbs so have less than 50gm a day. I personally experimented between 50gm and 130gm, settling for 90gm +- 15gm each day. In order to monitor my carb intake, I got an app. There are several online, including MyFitBit and NutraCheck which I use. I fill it in every morning and keep kitchen scales and a clear glass bowl on my kitchen top.
The other issue is that you need to know what foods affect you, as again that is different for everyone. As a Type 2 you are usually not offered a glucose monitor, so many of us fund our own. I think the GlucoNavil is suggested but I'm sure someone will point you in the right direction. It is suggested you monitor immediately before and 2 hours after first bite of eating, so you can see how much your blood glucose has spiked. The increase should be no more than 2. That way you can identify which foods affect you. I can take 2 small new potatoes, or one slice of wholemeal bread from a 400gm medium cut loaf, but rice, pasta, apples are lethal for me. Once I worked out what I could and should not eat, I reduced the testing to new foods.
You soon get used to portion sizes which can seem small at first, but I fill up with lots of above ground veggies like cauliflower, runner beans etc. Many people find substitutes such as cauliflower for mash and rice, courgetti or boodles for spaghetti or noodles, roasted squash for chips. There are low carb breads and lower carb pastas on the market - some people like them, others don't! All trial and error. The most important thing is not to go too drastic reducing your carbs at first, as it can affect your eyes. Various suggestions have been made, such as reducing by 1/3 for a few weeks, then again until you get to your desired level, and where you feel OK.
There is a food area of the Forum where you will find lots of meal suggestions and recipes. Most difficult is usually breakfast, as the usual toast and cereal is not good for Type 2 diabetics. Greek yogurt with a few berries and seeds is a popular choice, as is eggs such as a veggie omelette. I usually have a salad or home made soup at lunch, and in the evening have 2/3 plate of veggies, plus a protein source like baked seafood, grilled chicken. But I'm quite a boring conventional cook.
You say you are Type 2 and have been prescribed Metformin. That is the most commonly given drugs for Type 2 and it can have side effects. This can be difficult if you are a working person. If you are getting lots of cramps, the runs etc, which don't settle after a few weeks, you can request the slow release version, or there are other drugs. If your HbA1c is below 60 you might request trying to reduce it by lifestyle changes alone. I was initially successful, but became ill (unrelated) and had to medicate.
Regarding notification, I'm sure someone will advise you of the legal requirements. I did notify the DVLA, and the insurance companies for driving and my holidays. The DVLA sent me for their specific eye tests and my licence is renewable every 3 years, but I am 72. You should also be in the system for regular checks of your eyes for retinopathy and feet for neuropathy. Your weight, BP and cholesterol will also be regularly monitored, as will your HbA1c. I was initially monitored every 3 months and am now on 6 months monitoring. Most people are annual but my illness screwed up my results. I have a very good GP but not all are as lucky.
The other way you can help yourself is to tackle your cholesterol and BP. These high readings don't necessarily mean you are overweight, but if you are, you should try to lose weight, and you should certainly look at your exercise. I have familial hypertension, so have been on medication over half my life, even when I was a normal weight. I am required to do home monitoring every 6 months, so bought an armband home monitor kit (I have White Coat Syndrome at the GP or hospital). You will probably be offered statins for your cholesterol. Many people take them quite happily, but some, like me, have adverse reactions. What my GP suggested was to take a mini cholesterol lowering drink every day and it did work for me.
I had been an active sportsperson until my mid-60's when my hip gave out. My GP suggested aquafit, which I now do 3 times a week which has helped. My neighbour in his 80's cycles a couple of times a week, other friends go for daily walks. Of course there are gyms, but you can also exercise at home via videos if you prefer to be private (and save money).
This is a very long post but I hope it gives you some insight. Please feel free to ask any questions - we have all been where you are, and there's no such thing as a silly question. Best wishes.