What prevents me to create the longest chain and multiple nodes, and deceiving everyone?
Contrary to popular belief, Bitcoin does not use the longest chain. This is because of exactly the scenario in your question. Instead Bitcoin uses the chain with the most cumulative work. This is calculated by summing the difficulty of each block in the blockchain. If you made a blockchain that has more blocks than the current main chain but has blocks at a lower difficulty, then your chain won't be accepted because it has less work than the main chain.

You would have to have a chain that is so long that you have done more work, or have blocks with a higher difficulty so you have done more work. Either way, more work is required and that is prohibitively expensive.