Which part is giving you trouble?
A catalog helps you find the film. A viewing player supplies playback controls. A streaming server delivers media to that player. A mirror is another site address or copy. These terms describe different things, even when a search phrase puts them together.
Watch now is the viewing handoff
Tamilrockers opens JustWatch options for the title and country you chose. It does not display a row of numbered on-site movie servers. If playback fails later, use the controls and support of the service playing the film.
For repeated buffering
Test whether other titles fail too. Lower quality temporarily, reduce competing network use where possible and try the same service on another supported device. If only one movie fails, report that specific title and edition to the service instead of repeatedly changing unrelated browser settings.
If the failure happens before any viewing page opens, return to catalog troubleshooting. If the page is fine but dialogue is wrong, inspect the audio and subtitle tracks.