A drum ‘n’ bass beat is usually defined by putting the snare drum on the second and fourth beats of the measure. Use 2 kicks, two snares, hi-hats, closed hi-hats and a crash cymbal or something similar as basic rule and then use whatever u feel add’s to the rhythm add this into Ableton’s Drum Rack and loop it. Here is a 10 bar loop but it doesn’t have to be this long. Use Ableton’s session view like a sketch pad for looping until you get the results you like.
Here’s a tutorial making a drum n bass beat pattern within Ableton Live 10.