Hey People,
I am really improving my lead skills through pebbers scale, arpeggios,chromatic and picking courses.But I feel kind of stuck in rhythm guitar. i have adequate chord knowledge.but I am not able to improve my rhythm skills ..both with pick and with finger picking...how do I come up with new rhythms..can you please suggest me a drill to improve.

Maybe you could try a method book. I have "Blues Rhythms you can use" didn't work with it much beyond the first few chapters but seems to be pretty good.
You can search for it on youtube and see some people doing the lessons from this book.

Got to start on the most basic strum patterns. But, if you're missing them, is probably because you're having difficult with timing, like counting the beat or even changing the chords in the right time (which is a great part of rhythm guitar).

I would start everything from the beginning, doing all all down strums for a full beat, them changing chord, doing it again and them changing chord again. Going E, A, D might be good for the ears (all open, simple chords, but anything will work). Just practice that for a few minutes, a metronome might help.

Once you get that down, it's time to add up the difficult. On the "and" beat, start adding up strums, one of the most basic patterns is this: Down Up Down Up (miss) Up down Up Down. The trick is to get the right hand moving in a rhythm and without any stop. After that, you can try complicating things even further.

As long as fingerpicking does, this might be more complicated. First you have to get the technique down pretty good, going thumb, index finger, middle finger and ring finger while picking the strings. After that, the idea is to do an arpeggio (picking each note separate) of an chord and keep "moving" to the other ones.

A few good songs to help your strumming technique are these: Knocking on Heavens Door, One (U2 - even the simplified version will help) and Hey Joe (Hendrix, but only the chords not the whole embellishments with pentatonic and other scales).

For fingerpicking, I really don't know anything super easy, but Stairway to heaven can be a good start and even a good challenge for someone who's initiating in guitar.

Hope this helps. If all of this sounds crazy, I'll try to explain things a little better. But I'm sure other people here on the forum can give a better answer.