You don't need to have fear in you if you want to invest in bitcoin because it's not a ponzi scheme but a long-term investment that you can take your time and build your investment portfolio based on the amount of discretionary income that you have. Are you not use to saving part of your income for a long time just to buy something of value to you.

In the beginning since you are scared but love to invest, you can start with little amount of money like $10 and buy regularly every week with DCA for   while you continue learning about bitcoin. When your faith in bitcoin becomes strong and your believe in it has increased, you can choose to increase the amount of money that you are using to DCA weekly to an amount that will not affect you, so that you can accumulate more bitcoin than before overtime.

One thing you shouldn't ignore is setting up an emergency funds to back up your bitcoin investment. You can set this from part of your discretionary income by using half part of it to build your bitcoin portfolio and the other part for your emergency funds simultaneously. Your emergency funds should be at least three months of your salary so that when a real emergency comes, you wouldn't be scared but use your emergency funds on ground to take care of it.

It's better to start right away with little amount go build your confidence in bitcoin than waiting and not investing because of fear. Make use of the opportunity that you have now because tomorrow might be too late. The future of bitcoin is bright and if you invest from now to 10 years time with consistent buying and hodli, you will be among those smiling in future that you took the bold step to invest now.

You don't need any knowledge on shitcoins because it's useless putting money on them as you will run at loss in the long run.