Where to place unique tracking code for ad conversions?

Hello,

I am trying to place some tracking code into my theme. It’s a tracking code from a company I’m using for ads/google shopping and they have their own code for tracking. I think I’ve got the first correct - it is meant to go in the on each page, but if I’m right doesn’t think just go on the theme.liquid ?

The other is code to go on the thanks for order page, but I don’t know where this is. Would someone be able to help and tell me where this code should go after someone has purchased to track the purchase please:

Many thanks

If you are just tracking conversions, add the whole code in additional checkout scripts: https://help.shopify.com/en/manual/orders/status-tracking/customize-order-status

If you are stuck, get in touch with your tracking company to ask for advice.