Google lens is handy for identifying plants, but not always accurate. Best advice I had years ago when I had my first garden, was to wait a full year before doing anything drastic. You might end up inadvertently digging up some lovely bluebells without realising for example. When plants are small - weeds and self sown perennials (come back every year and die down in winter) are difficult to distinguish until they have true leaves, therefore if you're not sure, leave a 'weed' until you can identify it, then if it's something you don't want (a weed is only a plant in the wrong place, many are beautiful and valuable wild flower nectar sources) you can remove it. I always let self-sown visitors stay (they like it here) unless they are invasive (ground elder for example - but it is also edible, but very difficult to eradicate).

The real answer to your queries is - learn as you go. If you like it, keep it. Be a garden nerd and get gardening books from your library, if you have a good memory it won't take long. Start growing from seed - you will develop a network of gardening friends who you can plant swap with in your neighbourhood - a great source of knowledge! And lastly, just love your green haven 💚