No, you can't delete Safari. However these are the common problem why Safari isn't working.
- Too many tabs opened
- Too much cache, downloads, and history logs that have not been cleaned for a long time
- An extension, plugin, or website you're browsing is causing Safari to crash/freeze
- An outdated version of Safari
- Older version of macOS
You can do this if ever:
Close all tabs (Open Safari > Close all tabs)
Clear website data (Go to safari > Preference > Clear data)
Check Updates (About this Mac > Check updates)
Or lastly, Remove website data from Finder
- Go to Finder.
- From the Go menu, select Go to Folder.
- Enter ~/Library/Safari and click Go.
- Remove all files that contain History.db in their name and a file LastSession.plist.
Those are just suggestions. Up to you mate. :)