Floating node error in orcad pspice
These errors show that the specific nodes are floating, i.e they're just connected to one component, and aren't creating a complete circuit.

ERROR(ORPSIM-15141): Less than 2 connections at node N3449149.
ERROR(ORPSIM-15141): Less than 2 connections at node N3448272.

One particular strategy that I recommend for beginners is if you get an error like this, try moving the components that the error is for just a little bit. If the wires are properly connected, the wires move along with the component.
Another common mistake is accidentally putting multiple components on top of each other, which leads to a floating node error, which isn't easily seen sometimes.
You should put a little time into understanding the PSpice syntax that is seen here. It gives you the information about where the error is, and you can focus on these specific components.
TL;DR Try moving the op amp and checking the connection for pins 3 and 4
If that doesn't work, check if the op amp sub circuit is present.