Antonio, I have just edited my post above by adding more details to it.
Could you please re-read it first? And then you will decide what to use here: "I don't want to go to that party because I will get bored". I hope you can do it yourself after reading my explanation If not, then I'll help you of course.


More tips for you (I'll try not to use English words like "bore, boring, boredom" since they are ambiguous):

"надоесть/надоедать" - the key point here is you want something to stop, to disappear: you want someone to leave you alone, or you want to stop doing something, or you want to leave some place, or you want to get rid of something. Reason: you just do not want it to continue. There can be many possible reasons for that (physical tiredness, emotional tiredness, you lost your interest, you just dislike it in general etc.).

It is considered as "change of state": before you might be OK with it. But suddenly you feel like getting rid of it. You are reading, reading, reading (everything's OK), then you suddenly say: "мне надоело читать" (you do not want to continue). Reasons can be different. It is quite possible you will resume reading later after having some rest.

It may or may not be "скучно".

"скучно, скучать" - the key point here is lack of interest: it can be lack of interest to anything due to your emotional state (sadness, melancholy), or lack of interest to something specific because it is monotonous, or uninteresting to you.

It is considered as "state", not as state transition: if something is "скучно", then it was and it will be "скучно". Although you can specify "стало скучно" if you need state transition (it became uninteresting at some point). If "Эта книга скучная / Мне скучно читать эту книгу", then I guess most likely you can realize it with the very beginning of the book. And it is most likely you will not resume reading it after you decided to stop.