Welding Tips and Tricks

DIY gym bench iron frame board
hi sorry if I disturb, I should make a gym bench for weight lifting training, the one that is used to train with gym barbells and dumbbells.
surfing the net I saw that the dimensions should be roughly:
12 inches wide / about 30 centimeters wide
48 inches long / about 120cm
about 17 inches / 43 centimeters high from the ground
could someone suggest me how to make a similar structure?
the boy is about 185 centimeters tall and weighs about 90 kilograms, if some user friend had made one even with cheap recycled materials, robust, light and aesthetically pleasing I invite him to write thanks greetings to all.

I did the same about 8 weeks ago. I used:

50mmx50mmx3mm tubing. I drilled 30mm thru holes on a 50mm spacing. These are for the safety pegs. I used 30mm round stock for safety pegs.

Clean all the mill scale to a bright shiny metal, weld with whatever process you prefer.

I should add, the darn thing weighed about 240kG when finished. Enough of a workout to move it, let alone use it.

thanks for your precious intervention, if I don't ask too much and I'm not too petulant you could send me some photos of the artifact, sorry again if I'm boring and thanks for the valuable suggestions.

I don't take a lot of pictures of my "projects". This is a picture off the internet that is very similar to what I welded using the material listed above.

thank you for your valuable intervention, honestly a structure would be enough for me, a frame that is easier to make and use, but sturdy and safe, thanks anyway you are very ingenious you are a real talent builder. Thanks again

https://youtu.be/V2h6PbzVSdc