Hi italo_nascimento,
There is no any options to disable pagination. It needs code customization or you need to hire a developer to remove the pagination from index page.
Also you can increase a post number to maximum from dashboard -> settings -> reading -> Blog pages show at most. Change the default value 10 to some thing like 100. Then it will display all your 100 posts on the same page without pagination. For this you don’t need to create a child theme.
Thank you
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