negative thoughts

So throughout my 1 year I have been experiencing waswas at different levels and I didn't exactly make the best decisions. However this Ramadan is the time I will make my self one of the best and yes that does sound cocky and all but I want to strive for Allah and trying to be the best does sound like a good goal. Of course I won't be perfect that would be impossible only the prophet saw reached that perfection.

Anyways I have only one problem and it is the fact that recently I have been getting more doubts and evil thoughts whenever I think of Allah or say something about Islam my mind says something evil and negative about my religion sometimes making fun of the Quran or just straight up denying Allah even though by mouth I say the opposite.

So how do I combat this because I don't want these evil thoughts even though I feel lazy and empty inside I just want to be good to Allah. Like sometimes I say something like "I believe that Allah is" and then my mind thinks of something evil and which halts me in my tracks however what comes out of my mouth is good and sometimes evil tries to come out of my mouth by I make sure to stop my self before uttering it.

Sorry for the long text