GD pups are all on monthly Nexgard for fleas/ticks and six monthly Drontal for worms. None of mine have had ill effects from either. I give Tatze the same to keep it simple. My Cavaliers used to get lots of ticks - strangely easy to find in their long hair. I think because they adored charging through long grass. Touch wood, Tatze has never had one. .
I use advantix. But I came across this....I think it is rather expensive. I also couldn’t find the ingredients or other information. Didn’t discuss this either with our vet.... https://www.finecto.com/en-gb/hobby
Our two year old uses Bravecto. I'm not sure what our puppy (8 months) uses. My mom knows, but I remember the last time we went to the vet, he recommended something else for the puppy.