I went through a long period of not reading any books, not because of anxiety, though. Try reading with something quiet going on in the background, like a white noise machine, a piece of instrumental music (any genre but something calm and not focus pulling), or a sound effects website that offers various types of soundscapes you can test like this one: https://mynoise.net. I found a few soundscapes I liked and usually have one of them running in the background. I find that it relaxes me and makes it easier for me to concentrate and stay focussed on the book I'm reading.