Check your settings. Make sure you have the latest version. I have no issue opening links from email in the browser. Try clearing the app cache. If that does not work, clear the app data - you will have to reconfigure all your settings again.
Just so I understand, you have Samsung internet as your default browser, and when you click a web link in your email, it won't open the link? All links? It's possible that it's a misconfigured link, or a malware link. It could be that if you have app protection on, the phone's protection is preventing the links from opening.
Also, you can use any browser you want, you are not limited to Samsung internet. So set another browser as your default and see if the links open in that browser. Chrome, Edge and Firefox are all available for download. Chrome may already be on your device.
