random sampling TIME SERIES DATA taking into account the time constraint for a linear regression

Hi Everybody!

I have a dataset with time series observations and I need a code that allows me to select a random but ordered sample of data for a given lenght (Chosen by me).

I cannot choose just random observations because I have time series data. So I need to extract randomnly a block of let's say 2 consecutive hours of observations.

Thank you for the help!