First things first: why does the wedding matter? What does it bring to the story and why does it need to be the first chapter of your story?
The wedding itself is not going to be [shouldn’t be] the crux of your opening. What matters much more is what happens during that wedding? How do your characters feel about it? Who is getting married? Why are they getting married?
If this is just a regular wedding with nothing other happening than two people in love starting a life journey together, it really is not the best place for you to start your story. There probably should be some kind of conflict. For example, the bride is terrified of getting married and decides to run off, leaving the groom standing at the altar. Maybe a woman is rethinking her life choices after being asked to be a bridesmaid at her 27th wedding. Maybe the bride invited her three potential fathers without telling her mother? [tell me you recognize these plots] Maybe this is from the point of view of the maid of honour who is heartbroken because she’s in love with the bride but can’t say it any more.
So sort out first why the wedding is where you need to start and what would make it interesting as the introduction to your story and your characters.
As to the wedding itself, there are as many different kinds of weddings as there are couples having weddings or people dreaming/planning/imagining weddings. So ask yourself what kind of wedding your characters are having? Is it a religious wedding (research religious ceremonies of the faith your characters marry according to/ or invent them for speculative fiction settings) or a civil wedding (research legal requirements and administrative organisation in your setting). Are they the kind of people who will have 500 guests at the wedding? Or would they just elope or have a small wedding? Do they have money for a big reception or would they need not to spend on something lavish or frivolous? What kind of setting do they have available where they live for their wedding or can they travel? You probably wouldn’t have a beach wedding if you lived in Nebraska for example.