Modbus v2 - Beginner Question

I am a little confused with “things” and “items” for modbus.

I created a Thing for the connection to my heatpump. This works.

Now following an example here on the forum would mean I have to create a poller thing for every single modbus adress I want to read. That would spam a little my “things” and brings me to the question if that is really they way I should go or is there a way to create eg 1 thing “Heatpump” and then create many items to the read the different modbus registers?

based on that example:
Do I need to create “Thing data” for all registers or is there another way?

Nope, you can create a poller bridge thing for each block or span of registers that you want to read. Each block has to be of similar register type (e.g. coils, holding)

Yes, because that’s the only way for openHAB to determine how to interpret the raw modbus registers - signed, unsigned, float, etc.
If needed, you also define write details here (which might not be the same as read - some modbus devices are weird)
You only need to data things for the registers you interested in, you might leave “gaps” in a poller’s block.

Creating each of these data things makes channels available. You can then bind Items to channels.