Hi
For part number 1, you can do the following:
1. Use the Revolve Boss/Base feature to make the horizontal pipe
2. Use Extrude Cut to make that curve step in the horizontal pipe
3. Create another Revolve Boss/Base feature for the skew pipe(no need for an extra plan)
4. Create the rest of the part with Extrude Boss/Base, Cut and corner treatment features.
I hope this helps.

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