All these metal grooves are intended be played with a double bass drum pedal. You should already have done a lot of work with the double bass drum pedal before attempting these. If these look too difficult you could try 8 Intermediate Metal Double Bass Drum Beats.
There is a mixture of blast beats and simple double bass drum beats on this sheet. Play them all slowly to start with and then keep building up the speed. Ideally, use a metronome to record your progress, and practice this sheet over several weeks at least.
Related: Metal Beats – Part 1