yes it is normal you clearly had a very strong bond with your dad and you may find you come to a point when you say you are fine and actually you arent and a lot of the people you think have moved on may be doing the same thing.
Others here and myself have often found the second year really difficult add to that the year we have all had in 2020 and it doesnt help either .
We expect it in the first year - all those anniversaries- Xmas, birthdays etc ahead - but our culture has this year of mourning illlusion - and illusion is all it is - invented by the Victorians for reasons of convenience -but it is so ingrained we imagine it will be a magic goalpost and eveything will be better once we get past the first year and we look around and see those "moved on" people and think something is wrong with us and how we are grieving but it isnt the case grief is very personal and the relationship we had with the person who has died is never exactly the same as it is with others - not that its any less or greater just different.
Instead of thinking you should move on which suggests to move away from some-one and think of them as lost too us - i find its helpful to think in terms of moving forward which doesn't mean moving away from them but taking them with you just in a different way - whether that's through your memorys of his life - the things that made you smile or cry even little things that were annoying at the time - or whether its through a religious - or afterlife belief it doesnt matter moving forward just means taking them with you - going to the cemetery is fine there is nothing wrong with that at all but we are all different in that way as well and have to find what heals us ourselves -i dont have a headstone to visit but for me that would be focussing on the end of some-ones life and for me we are much more than tha time - we need to be some-one who lived and thats how i would prefer to be remembered with smiles not tears if that makes sense.
For me it was going to the places me and my husband loved and planting wild daffodils as an affirmation of him being there and perhaps making others smile on seeing them when they have a bad day and the being out in the natural world which was important too us both as well - then it was doing some of the things we talked about doing but didnt get round too or things he would have liked to do that were not things i would have done but i was doing them for him - and you dont need to do this alone maybe once lockdown is over take your kids to the places he took you when you were small and talk to them about those times - so they get to know him as he was when he was younger and in sharing those happier times you start to feel close to him again yourself.