NY will give you a credit for most of what you pay CT. But since NY has a slightly higher rate, there should be little tax due at tax filing time. You can do a rough estimate based on these tables:
https://www.forbes.com/advisor/income-tax-calculator/new-york/#:~:text=The%20state%20income%20tax%20....
https://www.incometaxpro.net/tax-rates/connecticut.htm
There is no underpayment penalty if you owe less than $300.
