Hi all I have 2.5tdi auto

When I brake after driving it for 20mins I get weird noise from only my passenger side

Sound and fetal like tight and squiking

I wonder if I have to change my brake fluid but when I open the tank I just can't see the fluid due to what looks like filter

Maybe your disks are damaged?

I would advice you to go to specialist and he can meassure disk tickness, becuase he can be uneven, and that may result somekind of noise and shaking steering wheel.

You should see the fluid from brake reservoir. Take off passenger side wheel and check for disc / brake pads wearing. Possibly you could have sticking brakes (brake cylinder don't move correctly and gets stuck).

discs ok,

pads ok,

fluid may be needs changing

but the noise coming only from right passenger side ...

may be the calliper...?