How do i download the Unreal Engine 3 based UDK?

Hello i am a hobby leveldesigner and can give me the Unreal Engine 4 afford each month.
are there any routes yet to get the old UDK?

The UDK is still available: Unreal Engine 3 Features - Unreal Engine

However it is encouraged that new projects start with UE4 (see the “Transitioning from Unreal Engine 3” section of the FAQ: Häufig gestellte Fragen - Unreal Engine).

Also, if cost is an issue, you can pay $19 once to get access to UE4 and then cancel your subscription. This will let you keep and use what you have, but you’d need to pay again to get any updates after the first month.

So If I pay the subscription 1 time, the next month I can still use the program to learn and test things?? (sorry for my english, i´m spanish)

Yes, when your subscription lapses you can still use the version you purchased. Like Jamie explains above.