I forgot the passcode for my iPhone.

If your iPhone is no longer accepting passcode entry attempts, and is not offering you the passcode reset option, the only way back into the phone will be to reset and erase it. All data that exists only on the phone will be lost.

You say you didn't make a backup. Hopefully you were using iCloud Photos. If you were, the phone would have been synchronizing copies of your photos to iCloud, and you could see the photos by logging into iCloud on the Web, or by turning iCloud Photos back on once you reset and erased your iPhone.

With regards to Notes, I believe that those can be synchronized to iCloud or to email accounts. Those Notes that were so synchronized might survive the wiping of the iPhone.

Have you tried to use passcode reset?

If you forget your new passcode, use your old passcode to unlock your iPhone or iPad within 72 hours - Apple Support

If you cannot use that I am afraid that you have to reset your iPhone Use a computer to reset your iPhone and your passcode - Apple Support

For the backup: are you using iCloud Photos? If so, you can find your photos back on iCloud even without a complete backup

If the passcode is not accepted by your iPhone, it is possible that the passcode you are entering, although correct in your memory, might belong to a different device. Passcodes are device-specific and cannot be used interchangeably across different devices. For example, if you have multiple devices and each has its own unique passcode, entering the passcode of one device on another will not work. Always ensure you are using the correct passcode associated with the specific device in question.

Your data is not lost if you have a backup either on iCloud or iTunes.

If you see an iPhone or iPad unavailable message or a "Security Lockout" screen

If you forgot your passcode, you can use your Apple ID and password to erase and reset your device without a computer.

Learn what to do if you see "[Device] unavailable" or "Security Lockout" on your iPhone or iPad.)

iPhone is disabled.

Following this process is the only way out if your iPhone is disabled. The steps given in this link will help you reset the passcode -> If you forgot the passcode for your iPhone, iPad, or iPod touch, or your ...

Regarding your data…

1. If you have an iCloud or iTunes latest backup, then there is nothing to worry about. If not read more...
2. You have synced your data to iCloud, then what you will get back is what you have synced to iCloud and uploaded to iCloud Drive; the information that is synced and stored in iCloud are, Contacts, Calendars, Bookmarks, Mail, Notes, Voice Memos, shared photos, iCloud Photos*, Health data, call history, and files you store in iCloud Drive. (*-If you have turned on iCloud Photos, your content is automatically stored in iCloud.)
3. You have imported your Photos and videos to Mac/PC then they are safely residing there on Mac/PC
4. You have uploaded some of it to Cloud Drives using the Files app (iCloud Drive, Google Drive, OneDrive, DropBox, Flickr, box, AmazonDrive, Adobe Creative Cloud, etc). The data remains there.
5. If you have not backed up or do not have the latest backup, nor imported nor you have synced or uploaded your data to cloud drives prior to the situation that you are in, then I am sorry, all your data is lost.

Welcome and thank you for reaching out. 🤗

To unlock an iPhone after forgetting the passcode, you need to erase it and restore it.

Use Apple’s official guide: If you forgot your iPhone passcode for step‑by‑step instructions.

Learn how to restore your iPhone from a backup for step‑by‑step instructions.

If you need more help, contact Apple Support directly.

Good Luck! 👋🏼😉

Smiliñ 😎 Brian | Community Volunteer