For most people who get dentures it takes around a month to get used to wearing and using dentures instead of your regular teeth.
For some people it may take around 2 months or even 3 months to fully get used to wearing the dentures as it just depends on the person.
Although within one month you should be at least partially used to wearing the dentures but it's normal if you're not used to the dentures in that time frame as it just varies from person to person.