car doesn't have generate enough power to move?

I have seen this many times. It is more than likely one of two reasons. First it can be a restricted exhaust, so we need to test the converter to find out if this is the issue. Here is a guide that will help with this.

https://www.2carpros.com/articles/how-to-test-a-catalytic-converter

Here is a video that will help with low power, but this sounds a little different then low power.

https://youtu.be/U1RoG3I-Oww

If the exhaust is not restricted, then I am pretty sure that this is a torque converter issue.

I have seen many times where the converter is not able to transfer the power from the engine to the transmission. Basically, the vehicle will be able to move as long as there are no hills or anything that the vehicle needs to overcome other than just the breakaway force of the tires. Basically, this feels like the engine has no power and is bogged down when trying to accelerate up a hill.

I am attaching the info below on installing a converter. Please let me know what questions you have and we can go from there.