guys which position should i play first

You should try every role with some of the easiest characters. But if you are a newbie you SHOULDN'T start with the top lane.

I think you should start with an easy champ. You should start with a support maybe.

definitely support

support is easiest for new players

Dont play support, definitely not the easiest for new players, it requires actual strong team work and game awareness since unlike other roles, you can not deal enough damage in a team fight or in your lane and call it a day. Easiest role is definitely top lane, with a tanky class, it's relatively more peaceful than other lanes, leaving you much needed time to practise basic skills such as effecient farming and timing