I don't quite get what you mean. The bottom left button does pull up the window for National Technology. However, you need to have a lvl 5 capital city first before you can upgrade your tech.
For Conquest, there is a button for Diplomacy right above the National Tech button. It allows you to:
1. Donate resources to allies,
2. Pay your allies to enter earlier
3. Pay enemies to enter later,
4. Declare war on an allied or natural state,
5. Preemptively declare war on enemies,
6. Check which states belong to which faction,
7. Pay enemies facing near defeat to turn neutral and
8. Observe the number of turns left before an allied or enemy enters the war.
There are also other features for Conquest such as "leader" countries in a faction that do not have the option to pay them to turn neutral.
