No sorry I saw it and didn’t know to swipe down, it is no longer there but I’m not sure what it is. Sorry new to this and older
No worries. In Android, there are generally two types of notifications in that top bar. Status notifications (signal strength, battery level, volume/vibration status, etc) are on the right and require no action. The ones on the left are from your apps and often requesting some sort of action from you. I.e. When you get an email. To access these, you swipe down from the top edge of the screen to pull the shade open and see expanded views of those notifications. They should say what app they are from and preview what it's for. Tapping on it will then open up that app to whatever specific thing it's informing you about. I.e. Taking you to a specific email in your email app. Some can automatically dismiss themselves if it's a time limited notification.
The next time you see this, just swipe down. If you are still unsure, screenshot that (as long as it has no personally identifying info) and we could try to help further. You may also look through your app drawer and find that icon, which would tell you which one it came from. Not every notification icon will match the corresponding app icon, but it is the typical way things work and wouldn't hurt to check.