What is the fastest way to get XP in Dota 2?

The only way to level up is by playing DotA 2. Though after level 10 you can play ranked match which rewards you more exp than normal matches.

How do you farm like a pro in Dota 2?

0:289:12How to Farm Faster on Any Hero | Pro Dota 2 Guides - YouTubeYouTube

Which is harder Dota or LoL?

Dota IS mechanically harder than LoL though. With more item actives means more buttons to push. And some heroes have 6 skills like Morphling. However these simply come down to muscle memory after not too long.

How many levels are in Dota 2?

Heroes can gain a total for 29 levels, resulting in level 30 as the highest possible level a hero can reach.