In Al'Ha'iyyah L8 for example you speak about the innovation of making up your own Du'a. I dont fully understand, is it impermissle for me to ask Allah in my own words, especially if I dont know a dua for it from the Quran/Sunnah, and if I dont speak arabic? Jazak Allahu Khairan

Ustadh AbdulAziz al-Haqqan

Yes, you may ask Allah in your own words and in your own language. The innovation is inventing a fixed wording, number, or time and keeping to it as if it were a sunnah. Inside salah, say in Arabic what you can and the rest in your own language.