Hello Yes2Yoga,
Welcome to Apple Support Communities!
We want to help you sync your iPhone and Mac. You can use these steps to sync your devices:
"Sync all items of a content type
- Connect your device to your Mac.
- You can connect your device using a USB or USB-C cable or using a Wi-Fi connection. See Sync content between your Mac and iPhone, iPad, or iPod touch over Wi-Fi.
- In the Finder
on your Mac, select the device in the Finder sidebar. - If you connect your device to your Mac using a USB cable and don’t see the device in the Finder sidebar, see If your device doesn’t appear in the sidebar.
- Click the type of content you want to sync in the button bar.
- Note: If you use iCloud Photos and Apple Music, your photos and music are synced automatically using iCloud. When you click Music or Photos, no options appear for syncing.
- Select the “Sync [content type] onto [device name]” checkbox to turn on syncing for that type of item. For example, select the “Sync movies onto [device name]” checkbox to sync your movies.
- With the checkbox selected, syncing is set to transfer all items of that type to your device.
- Repeat steps 3 and 4 for each type of content you want to sync.
- The bar at the bottom of the window shows how much free space remains on your device after you sync. Move the pointer over the bar to view details about the content you’re syncing.
- When you’re ready to sync, click Apply."
This Apple Support page has the full details: Sync content between your Mac and iPhone, iPad, or iPod touch - Apple Support
Or if you're seeing a different issue like your computer not recognizing your iPhone, see here instead: If your computer doesn't recognize your iPhone or iPad - Apple Support
We hope these steps can help isolate and resolve the issue so you can connect your iPhone and computer.
Cheers!