best technique to remove noise from bio signal data
As a first appraoch I would suggest to use a mean filter, which will calculate the average of the last n values.

$$y[n] = 1/N \sum_{k=0}^{N-1} x[n-k]$$

If you have access to the full signal (offline processing) you can perform forward and backward filtering which will avoid the delay introduced by a single filter. (Check matlab's filtfilt function for example)