In Ireland, the State pension is currently paid from the age of 66. It is not means-tested and so, if you qualify for it, you can also work and still receive it.
However, the state pension is not guaranteed. To qualify, you need to have paid enough social insurance (PRSI) contributions. If you have worked in Ireland and paid PRSI at any time you can apply for the State pension and your claim will be assessed based on your contributions. The weekly value of your pension will be based on how many PRSI payments you have made.
If there are gaps in your PRSI record, such as when you were raising a family or in a caring role, these will be taken into account under new rules that were introduced since 2012.
The State pension is taxable but, if it is your sole income, you will be unlikely to pay tax on it.