if you are investing by just buying and then storing it then you can only wait for the percentage increase in the price of bitcoin, which you will never know for sure the increase is up to what percentage.
because crypto is not like a deposit with an annual percentage of clear value.
but crypto has a tendency to increase value better than other investment products
A lot of people do not even have an idea what the whole thing about investing in bitcoin is all about and what is actually the reason why they should be investing in the first place.
This is not something that is meant to give you a regular income, with the way the OP placed it, but it is something that you are believing in its long term potentials and its usage, knowing that at some point the value will increase, which even at that, you should never get greedy but only invest what you know you can just leave and not care about for the next couple of years, which in that case, thinking of income is something that has shown the limited knowledge the OP even has about the space.