I were hearing aids in i want to know if I’m aloud to change battery in shabas or yom-tov in also how about making the volume lower or higher
Changing the battery is problematic, because it is like turning the hearing aid on and activating it on shabbos. However you may ask a gentile to do it for you. It is important to remember to check that the batteries are either fully charged or that new batteries be inserted o the hearing aid before shabbos.
Regarding changing the volume, is permitted according to many poskim. The reason being is that you are not making any new circuit by changing the volume
I am attaching a very practical Kuntres from Horav M. Shuchatowitz, a posek in Baltimore and an expert on these topics, Toras Hacheresh He can be reached at 443-802-8559
Minchas Shlomo 1:9 p. 74 d”h v’al kol panim, Shemiras Shabbos K’Hilchasa 34-28, Lev Avrohom 1:6:(132), Be’er Moshe 1-17.