My understanding is that the Philistines were one of the “Sea Peoples” who were migrating, raiding and invading around the turbulent period around 1,200 BC, when there were widespread collapses of many old civilizations around the Mediterranean and Mid East (the Late Bronze Age Collapse). They settled around current day Gaza around the time of the collapse.
Canaanites were local people in the Levant (current Israel and Lebanon) before the collapse (who many centuries later developed into the sea-faring Phoenician civilization). Canaan was also the place name, so different peoples at different times could be described as from there (as Canaanites).
There were no Sea Peoples as such — they were the Greeks, and the conventional pseudochronology is wrong by hundreds of years.
Wow, talk about urban development and adaptive reuse!