I am 19 and put the correct birthday but it wont let me enter in the adult places.

[valerie Inshan]

How to change your preferences to view adult content

Even if you are 18 or older, you still need to opt in to view adult content. 

Log into Second Life, then follow these steps in the Viewer to set your maturity preferences:

1. Choose Me > Preferences (or Ctrl-P) and click the General tab.
2. Choose General, Moderate, Adult from the I want to access content rated: dropdown menu.

   

3. Click OK.

Congratulations! You may now visit any publically accessible land in Second Life, regardless of its maturity rating.

Note: If your preferences are not set to allow adult content and you attempt to enter an adult-rated parcel or region, you receive a prompt allowing you to either cancel the teleport or instantly update your access preferences to General, Moderate, Adult.

[valerie Inshan]

How to change your preferences to view adult content

Even if you are 18 or older, you still need to opt in to view adult content. 

Log into Second Life, then follow these steps in the Viewer to set your maturity preferences:

1. Choose Me > Preferences (or Ctrl-P) and click the General tab.
2. Choose General, Moderate, Adult from the I want to access content rated: dropdown menu.

   

3. Click OK.

Congratulations! You may now visit any publically accessible land in Second Life, regardless of its maturity rating.

Note: If your preferences are not set to allow adult content and you attempt to enter an adult-rated parcel or region, you receive a prompt allowing you to either cancel the teleport or instantly update your access preferences to General, Moderate, Adult.

[Ansariel Hiller]

Since you have a last name, your account seem to be older already which let's me think you registered for the Teen Grid back then. There are often issues with the automatic transition of old Teen Grid accounts where people turn 18. If Valerie's answer doesn't work, I would suggest to file a support ticket: https://support.secondlife.com/create-case/