Google Tag Manager is the great tool to apply and manage the pixel in your sites.
You can also add Integrate Pixel into Google Tag Manger by the following steps:
1. Firstly, you should create the tag, and you can find the Integrate pixel under here.
2. Secondly, add the new tag and submit it.
3. Last, you can add the submission configuration for the tag.
Feel free to let us know if you have any questions.