From which message can we get bandwidth part (BWP) in 5G?

Hello 5G Experts,
From which message can we get bandwidth part (BWP) in 5G?
And assuming BWP is the only active BW a Ue uses per carrier, how to interpret an UE served with 4 CA with each carrier of 100 MHz BW will the use 4x BWP or 4xCA BW = 400 MHz?

For DL it’s PDSCH config, and for UL it’s PUSCH config.

Thanks, got it from here:

Only one active BWP possible but 4 can be configured.

And assuming BWP is the only active BW a Ue uses per carrier, how to interpret an UE served with 4 CA with each carrier of 100 MHz BW will the use 4x BWP or 4xCA BW = 400 MHz?

4 x CA BW = 100 MHz.
Csi-rs ports are given to improve coverage by increasing SINR.
If you reduce csi-rs ports beam gain will reduce so SINR will be reduced.

I think you didn’t get my question.

4 x CA each CC having it’s own BWP.

In this case I shoul take 100 MHz as BWP since17875 corresponds to 100 MHz BW?