Q: Iphone automatically open apps

Did you already try the general troubleshooting steps?

1. Force restart the phone by holding the sleep and home button for about 10sec, until the Apple logo comes back again. You will not lose data. On the iPhone 7 press and hold the sleep and volume down button to force restart.

2. In case this does not work, set it back to factory settings, without using the latest backup. Test the phone. If it works, restore from the backup.

Use iTunes to restore your iOS device to factory settings - Apple Support

3. If factory resetting does not help, get the phone checked by Apple:

Start a service request

Find an Apple Authorized Service Provider

Make an Apple Store appointment