You can usually start with an up-to-date mobile browser. A browser route avoids installing software and makes it easier to confirm the current web address.
Android safety
Only install an app from a link you have verified. Do not download APK files from messages, pop-ups or unfamiliar file-sharing pages. Review the requested permissions and keep Play Protect or equivalent device protection enabled.
iPhone access
Use Safari or another supported browser and add a verified page to the Home Screen only if useful. iOS installation prompts outside the App Store deserve extra scrutiny.
Connection and cache checks
If a page stalls, switch between Wi-Fi and mobile data, close unused tabs and reload once. Persistent display issues may be resolved by clearing site data, but doing so can sign you out. Record any error before contacting support.