Hi @Lucie Jacques ,
Yes, Correct. As mentioned in this microsoft documentation , the current number of people in a normal teams meeting (can chat and call in) are up to 1000 participants with your M365 E5 license.
Source :
https://learn.microsoft.com/en-us/microsoftteams/limits-specifications-teams#meetings-and-calls
https://learn.microsoft.com/en-us/microsoftteams/limits-specifications-teams
Hope this helps.
If the answer is helpful and your question is resolved, please click "Accept Answer" and kindly upvote it ,so that it will be helpful to the other community users. If you have any further questions about this answer, please click "Comment".