Here are the instructions on how to tune in your TCL TV

1. In TV mode, press the SETTINGS button on your remote
2. Select Channel
3. Select Channel Scan
4. Press OK/► to enter
5. Press ▲/▼ to select Country/Region 
6. Press OK to enter
7. Enter the default password 1234 (or your own password in case you have changed the password in the System > Lock menu)
8. Press ▲/▼ to select your Country or Region 
9. Press OK to confirm
10. Press▲/▼ to select Scan Automatically
11. Press OK to enter
12. Press▲/▼ to select Channel Type
13. Press ◄/► to select Digital, Analog or Digital & Analog
14. After configuration is completed, press ▼ to select Search
15. Press OK to start scanning channels 
16. The channel search may take a few minutes

If your TV has slightly different settings, it's best to look in your manual for instructions or contact TCL directly.