Best Farm?

Where i Farm Best? I dont know :/

Depends what you seek

For gold, early on your best bet is to sit and play as many video ads as you're allowed; maybe watch some TV while doing this.

As you get up into Hell Difficulty you'll find the gold value of dropped equipment approaches that of a dropped video. However, well before that, you can spend 50 souls on infinite stamina and just run through a boss stage (ideally one where you can 1-2 hit normal enemies and not require any potions to regularly defeat the boss) over and over, selling off 99% of the equipment and equipping it if it's better than what you have. With dedicated play time (again, just sell items and restart on autoplay while jogging, watching TV, or some other primary activity), those 50 souls can net several million gold per day in Inferno difficulty, mostly from selling items.

For weapons, purchased weapons are based on character level, so I suggest considering leveling up (which, incidentally, is handled nicely by grinding for gold as described above) until you can buy a weapon 2-4 tiers above the best you get through enemy drops.

For experience, you gain significantly more the higher the stage you choose, so try to get as far as you can in the game.