First, try to clear the concept of blockchain. Second, try to explore existing applications or researches regarding blockchain which will help you to understand how they applied this concept to their model. Then try to select an area and try to impose blockchain in that area.
As Windson suggested, read that Survey paper. Its really good.
But to understand the current inventions using blockchain and tangle technology, check this website - www.coinmarketcap.com. It has the list of all the cryptocurrencies and tokens available in the market. Read about the tokens. Each token is an unique project created on top of various crypto platforms like Ethereum and NEO. By studying all the tokens, you will get an idea about the current blockchain Industry which will be helpful for you to come up with your own unique Idea.
Do you have practical experience with Blockchain tech? If not, then
the #Multichain tutorial:
https://www.multichain.com/download-install/
is easy to start and complete with Oracle VirtualBox, Vagrant and two virtual Ubuntu machines (Vagrant boxes). Thanks to Github heavyengineer/vagrant-multichain
Hi Emanuel, if you are looking for programming courses, you will find plenty of them on Udemy. If you are looking for the theoretical background, there is an excellent MOOC on Bitcoin on Coursera (from Standford University).