Hey guys so i was wondering why when i guard something sometimes ill get 10xp sometimes ill get 50xp nd evry so often ill get like 70xp?

Just sitting by the point you have to defend will give you ~7XP per tick.

Actively defending it - mainly: causing damage to enemies - will increase the XP/tick temporarily.

7xp? i get 50 for jus sitting by it

killing a person near objective gives bonus if some thing happens it stacks so you can be getting 50xp at a time

I think there are additional bonuses if you stay close to the objective for a certain amount of time as well.

And you get a small amount of credit for any damage dealt (or enemy downed) near the objective while you're also near it. If someone else kills a bunch of enemies next to the objective you're guarding, the next tick of your XP bar will be boosted because of it.