How did your puppy learn to indicate needing to pee?

We recently adopted a Pomeranian boy (he’s quite tall for a Pom so possible mix) when he was roughly 5-6 months old and have had him for two months now, so aged around 7-8 months.

He loves training — he can already fetch and drop the ball at my feet, he rarely barks at anything (except his toys and sometimes when alone for too long). He has never once woken us up in the night for toilet break, or had a night accident, and I can honestly say is the easiest puppy we’ve had. We don’t have any other dogs currently.

However!

He still pees (not poo) in our house and we are at our wits end trying to figure out how to stop him from going indoors, and how he can tell us he needs to go. Just leaves a puddle on the floor, (never lifting his leg inside, he only does this outside).

We got him a bell, but he only rings it if we physically present it to him. He knows that it is related to toilet time outside, but he doesn’t initiate the ringing and hasn’t connected that when he needs to go he should ring it. He occasionally goes near the door the garden but only 30% of the time.

He can hold his bladder for many hours during the day and night, no problem there.

He can pee on command on walks about 80% of the time.

We used to use pee pads but we feel that might have encouraged him more and he enjoyed destroying them.

He never pees inside any other building except our home (and friend’s homes). I keep track of his pee schedule, but if I have a 1 hour plus meeting, bam— pee on the floor. We use the enzyme spray each time too.

How can we help our puppy understand that inside our house is not the place to pee, and how do you teach your puppy when to tell you they need to use the toilet?