I'm not Maltese, my parents are both English but my father was stationed there when he was in the Navy in the late 50s and early 60s, my mother joined him for several ears and spent her pregnancy there. I was born in Mtarfa military hospital which I think is now a school but we lived in Birzebbuga.
So that we can form a visualisation for you it will be important for this to be open enough for you to feel comfortable. If anything about what I write doesn't feel right, just say so or substitute it for something which does feel comfortable. Anything that doesn't feel right will distract you from dropping down into the visualisation.
Take a moment before starting to think about your intention. To meet your Dad in a safe and secure way.
Like any meditation this is started by complete relaxation. Find a time when you won't be disturbed, take the phone off the hook and turn your mobile off. Find a comfortable way to sit or lie down where you can relax completely. When you are comfortable think about the top of your head, bring your awareness down to your eyebrows, knit them together and then relax - feel and understand the difference between a relaxed state and tension. Repeat this down the face, neck, shoulders, arms, hands, torso, stomach, buttocks, thighs, knees, flex the feet then the ankles and toes. This process of tensing and releasing the muscles takes time - that's fine, it should take several minutes and this also allows your mind to focus and filter out the mind chatter, bringing you down a little to a lower brain wave cycle. Don't skip it.
Take a moment to just be in this totally relaxed state, experience the deliciousness of it.
With eyes closed, imagine a place where you like to go, which feels safe and welcoming to you. It can be somewhere you actually go or a place from memory, somewhere in nature or a wherever you feel relaxed. What do you see? Can you smell or hear anything. What is the weather like? Observe where you are, looking at and enjoying being in your favourite place.
As you are looking around, you see a way forward in front of you. Everything feels safe, you feel happy and inquisitive without any worries. As you move forward what is the path ahead of you made of?
Looking up you see someone in the distance walking towards you. When you meet them say hello and ask them who they are. If this is not your father, ask the person politely if they know your Father and where to find him.
If you find yourself faltering, don't worry, you can revisit this visualisation as many times as you wish. If you meet your Father, I leave it up to you what you say, if not, leave it a day and try again, change part of the visualisation to something that feels more appropriate or if you meet an animal or plant who wants to help you, perhaps developing this relationship will later help you to find the answers you are looking for.
I hope this helps, but don't hesitate to ask if you have questions, problems or just want to talk. There are many people here on AT who can offer wonderful help and advice on different techniques.
Good luck.