Power plugged in but not charging battery and slow app simultaneously

Why my sp5 have 2 problems at the same time ?

What tools should I buy for replacing the surface pro 5 battery?

Power plugged in but not charging battery (stuck at 67% but when power is detached the device turn off immediately) and slow application simultaneously. These must be windows software problem and hardware . Already did reset windows with keep files option still very slow. Also message of saying The group or resource is not in the correct state to perform the requested operation error.

Hope you guys can help