Treat beliefs playfully; understand that limiting beliefs are not weighty impossible barriers. Deal with them as children with building blocks if they do not please you knock them aside and make new one.
Your thoughts have an electromagnetic reality; when you think in terms of abundance and plenty those thoughts draw to you abundance and plenty as a magnet does.
There will be a while, while you are changing your beliefs to the point of your present experience and so there may be physical lag before your new beliefs draw to you abundance. Your physical experience follows your thoughts. And you cannot change the experience without changing your thoughts.
It does not good to believe two things at the same time.