With the limited information here, it's hard to point you in the right direction...so I'll try my best.
- You are using the WordPress theme twentytwentythree or newer
The best way I've found to do this is by going finding the Template and overriding it. To find the default template for Blog posts:
- Go to Appearance -> Editor
- Go to Templates -> Manage all Templates (bottom)
- Click on Blog Home
- Edit the template how you see fit. (highlight the title and hit delete)
Again, this is based on the assumption you are using the twentytwentythree theme or something newer.