Hi Pedromaia17,
If you haven't done so yet, it's also a good idea to make sure your iPhone is running the latest version of iOS 16, since this can help with overall performance: Apple security updates. If an update is available, be sure to create a backup before installing it: Update your iPhone or iPad
From what the graph shows, it appears that the sudden drops in battery level seem to happen when your device is being used for 30-60 minutes. The Usage By App section shows that YouTube and Tik Tok are being used the most. When using some apps, specifically apps that are graphics-intense or when streaming videos, it's normal to notice that the battery may drain more quickly as opposed to when you're not using these types of apps.
The following articles have tips to help maximize battery life, and information on your battery:
Maximizing Battery Life and Lifespan
iPhone Battery and Performance
Since you mentioned that this sudden drop also occurs while the device is being charged, you may want to reach out to Apple Support directly so they can look into this with you further. They can be contacted here: Get Support, or by calling the most applicable phone number from this list: Contact Apple for support and service.
Cheers.