Not starting after removing catalytic converter P0050 code?

Does the engine crank and not start or, the engine will not crank over? When you removed the catalytic converter was it is pieces inside? If so, it could have clogged up the muffler and it won't allow exhaust to pass through it. I would disconnect the exhaust to see if it will start. The p0050 code should not affect the running of the engine, it just means the bank 2 sensor one oxygen sensor needs to be replaced. Here is a guide to help will the no start condition and I have included how to change out the oxygen sensor in the images below.

https://www.2carpros.com/articles/car-not-running-advanced

Clear the codes when the repair is complete. Check out the images (below). Let us know what happens and please upload pictures or videos of the problem so we can see what's going on.