First time flying out of states, need help with finding affordable tickets.

I’m planning my first trip outside the US and I’m looking at going to France for about a week maybe a week and a half. Still haven't picked when I wanna fly didn't book anything yet, wanna find an affordable ticket first.

So I wanted to ask how people usually find cheaper tickets for international trips. Are there certain sites, timing tricks, or things I should know before booking? Any advice for a first time international flight would be appreciated.