Get a copy of Mastering Bitcoin and Programming Bitcoin.
Do the exercises.
Write a micro library.
Subscribe to developer newsletters and read new proposals.
Attend technical conferences and meet-up's.
For all that, what programming language does Bitcoin use? C++
At the least, how do you write Bitcoin codes?
What is the salary of a Blockchain developer?
According to Hired, an average salary for a blockchain developer is between $150,000 and $175,000 per year. To compare, an average software engineer salary stands at $137,000 per year. The highest blockchain developer salary can be found in the San Francisco Bay Area – $162,288.
In short: It is not advisable to learn Solidity to only deploy a new ERC20 token. Instead, demand for Blockchain developers will increase in broader enterprise areas such as financial, supply chain, insurance, digital identity, land registries, government, etc.