@eliJUZP6
Step 1. Start a new file. Start a new sketch on the XZ Plane.
Sketch a vertical line from the Origin a length of 2.176 as shown below...
Right click on the line and select Centerline.

Now sketch a Horizontal line from the Origin to the right and a Vertical line from the end of the horizontal line...

Dimension as shown. The Ø6.00 diametral dimension is achieved by selecting the centerline.
Sketch a 3-Point Arc and dimension as shown (I had to guess the actual dimension as your sketch didn't make logical sense for this radius).

Now Revolve the sketch about the centerline.

Add a R 0.2 Fillet to the edge as shown below (it is almost always better to add Fillets as placed features on the solid body rather than in sketch. I had to guess on the Fillet radius as your model didn't make logical sense.

Turn the part over and run the Shell command selecting the bottom face to remove.
Enter the desired thickness.

Q1. Will this design only be 3D printed, or will it be fabricated from metal components welded/soldered together?
Q2. If fabricated from multiple metal components - will the attached components protrude through holes in this component or will they be flush mounted to the outside face (the pipe nozzles, not the hex fasteners - we will get to those).

Attach your progress *.3df file here for next set of steps.