Hi!
As humans, we are different. Some people like to talk a lot, and others have a quieter personality. Some love to talk about their faith, while others may find it difficult to find the words. Some can pray out loud for a long time, others think it's best to pray internally. It's all about personality, and what you're used to from home.
When Jesus taught about prayer, he said it's not about praying the loudest or using the most words: And when you pray, do not keep on babbling like pagans, for they think they will be heard because of their many words. Do not be like them, for your Father knows what you need before you ask him. (Matthew 6:7-8)
God hears us as much when we pray silently as when we pray aloud, because He sees what's in our hearts and minds. God hears our innermost prayers, even if they are not said aloud. It is good if we sometimes lack words. There are Bible stories of people who had many words and people who didn't have many words. Both are OK!
Some stories (the Pharisee and the tax collector in Luke 18:9-14) show that God looks at the heart when words are sincere. The Pharisee used loud words to impress, the tax collector whispered a small sentence. Then there is David, who had many words and wrote long prayers that can be found in the book of Psalms. These are prayers that have helped many!
If there are several of you together, it can be good to have the confidence to pray out loud. This way others can hear what you're praying for, and it's easier to participate in each other's prayer requests. Some people take a little time to get used to this, and that's natural. It's nice to start in a safe and small environment. Many people find that each time they try to pray out loud, even if it's a small prayer, it feels easier.
In a relationship, it's good to be able to pray together. Maybe you can pray the Lord's Prayer together? For many people it feels safer to pray a ready-made prayer where you don't have to think about what to say. Perhaps this can make it feel more natural to say your own prayers. Often it's easier if you agree to each say your own sentence and then take turns, then you don't have to formulate nice and long prayers, but can say a short sentence as you go.
We would like to wish you the best of luck.
Kind regards BoyandGirl.info