we have a bfp with 17bar suction wh

If you want people to understand what you are asking do not use abbreviations or acronyms.

I'm guessing bfp is Big F'ing Pump, but that's probably not enough to go on.

Every pump question that asks "changes in piping" needs to include the pump curves, the current piping sizes, any fittings, bends, elbows, and so forth or just, you know, the bare minimum of measuring what the loss is at the target flow rate to make any estimate of whether that loss can be reduced enough.

I am also concerned that I have no idea where any of the mentioned pressures are supposed to be in this system. Does the Booster pump produce 17 bar or does it produce 10 (some units) of pressure head?

Completely lost as to what a "da" might be or how it could be elevated, but at least it's given that elevating the da is not an option.

I'm working on bfp being Boiler Feed Pump.

You can't create pressure without doing work, I.e. gravity or a pump. Changing pipe layout is not going to do anything to increase pressure from 10 bar to 17 bar.

Your BFP may be able to handle a reduced inlet pressure, but maybe not. You need to look at duty requirements, pump curves etc

Remember - More details = better answers
Also: If you get a response it's polite to respond to it.

Keep this current arrangement with NPSH booster pump. Your main BFP must be working well. But I dont know why your booster has to create 17bar of head ( since your DA must be operating near to atmospheric pressure ?); 3-4bar should be more than enough.

But why do you want to change ? Not enough NPSHa for booster pump ? NPSHr for booster with 3bar diff pressure would be much less.