Check the following Apple articles:
Connect to Wi-Fi on your iPhone, iPad, or iPod touch
Connect to Wi-Fi on your iPhone, iPad, or iPod touch - Apple Support
If your iPhone, iPad, or iPod touch won’t connect to a Wi-Fi network
If your iPhone or iPad won't connect to a Wi-Fi network - Apple Support
Check the route settings -> Recommended settings for Wi-Fi routers and access points
Recommended settings for Wi-Fi routers and access points - Apple Support
If you need help with your Wi‑Fi password
If you need help with your Wi‑Fi password – Apple Support (UK)
- You need to sign in to your router.
- The Wi-Fi network name, or SSID (service set identifier), is the name your network that has a password.
or If you have iOS 16 / iPadOS 16:
Go to -> Settings -> tap Wi-Fi -> tap on the hidden Password -> enter Passcode -> you will then see the Wi-Fi Password.
If they are On, turn Off Hotspot & VPN.
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i am using iPhone SE 2nd generation
Update your iPhone to iOS 17.