I do a lot of presentations for work. As everyone else has said, take your time and remember to breathe. And nerves are normal. Even the greatest public speakers must get nervous before they step onto the stage. It is ok.
If it is not too daunting you may want to record yourself - can just read an extract from any book. Get to understand your flow. Try talking slower than you would in a normal conversation.
This might sound weird but practise/prepare some fillers. Mind blanks, pauses, uumms and even nervous laughter are all part of normal speech. It is not a sign of failure (unless you brayed like a donkey for your entire slot then ok that’s a bit weird!!!). Get to feel comfortable with the uncomfortable of things.
What is your body language like? People are there to listen and watch you. Own your space and time. More often than not, everyone is rooting for you to do well.
Are you a human helicopter? Are you arms waving around everywhere? Consider holding something to encourage less flailing. If you do hold something make sure it’s solid - if you hold sheets of paper and shake from nerves the audience will see/hear that - stick your notes on something with a hardback.
You are a human, not a robot. Watch other people you think speak well to pick up some tips but there’s no need for you to attempt to be a carbon copy.
Some presentations I give are dry as weetabix out of necessity (I often deliver bad news) And that’s not a reflection of me. Sometimes I’m able to jazz it up a bit and shockingly I enjoy it nowadays. Like any skill, I had to learn and make mistakes along the way.
Some people say find a visual point to focus on. This may be useful starting off but nowadays I do try to look around and feed off the audience. Whatever suits you.
also prepare a closing statement. I’ve seen many good presentations that end awkwardly because it just trails off in silence. Have a “the end” type thing (or passing it on to the next speaker) ready.
And on that note, i think I’ve waffled on long enough! Hopefully something has been useful.
Wishing you the best of luck.
(Apologies for formatting - on my phone and have typed way too much.)