Partly. A hotel can see which websites you connect to, when, and how much data you use, but it can't read the pages, searches, messages or passwords on any site that uses HTTPS (which is nearly all of them now).
What the hotel network can see
- Domain names. Your browser announces the site name (the SNI field) in plain text when it opens a secure connection, and standard DNS lookups are unencrypted too. The Center for Democracy and Technology explains how SNI leaks the hostname even when the page itself is encrypted.
- Timing and volume. Login time, session length and how many gigabytes you moved.
- Your device. Its MAC address, device name and whatever you typed into the login portal (room number, surname, email).
What it can't see
The specific pages you open on a site, what you search for, the contents of your email or chats, and anything you type into forms. A hotel guest Wi-Fi vendor lists the same split: portals record your login details and usage, while HTTPS keeps the content private. Plain HTTP sites are the exception, and those are readable by the network.
So a hotel could tell you spent 40 minutes on youtube.com at 11pm. It couldn't tell which videos you watched.
How to shrink what's visible
Turn on encrypted DNS in your browser and keep your phone's private Wi-Fi address setting on. For the most coverage, connect through a VPN such as NordVPN: the hotel then sees only that you're connected to one VPN server and how much data passes through it. The sites you log into can still see your activity on them, of course, and a VPN doesn't protect you from phishing.