Please, could someone help me?  

RE: Please, could someone help me?

The printer still runs on the same g-code, you can just copy over the g-code you prefer.

RE: Please, could someone help me?

I Prusaslicer, enable "Expert" mode and go into the printer settings.  There you can enter your start and ending gcode that the slicer will use when you slice your STL file.  This will be part of the gcode export.

I hope the screenshot is enough to get you started -- you might have to open this image to see the full width of the screenshot.

RE: Please, could someone help me?

@clbears @egar

when I paste the Cura gcode into the Slicer, an error happens:
start_gcode
Parsing error at line 2: Variable does not exist
M190 S[bed0_temperature] T0

RE: Please, could someone help me?

@glauco-ramos

It's not liking some of variables that I guess came from Cura.  Prusaslicer has its own variable names.  For example, I know it has (at least) two variable names for bed temperature:  [first_layer_bed_temperature] and [bed_temperature].  One is for the first layer only, the other for all other layers.

A trick to finding the variables is to find the setting you want on one of the settings screens and let you mouse hover over the data field.  A pop-up will appear listing the parameter name.  Use that name for your variable.  For example bed temperatures are found in the filament settings page.

I'm sure they are all documented somewhere, but I don't know where that is.  I'm sure the more experienced users can help you out there. 

RE: Please, could someone help me?

I have never been able to get consistent results from Cura.  

RE: Please, could someone help me?

Posted by: @cwbullet

I have never been able to get consistent results from Cura.  

Cura was the first slicer I learned, but when I got the Prusa printer and tried it the results were disappointing.  Mainly the issue was some of the speeds, mainly the first layer, that were in the profile for the MK3S that came with the version of Cura I had.  Once I got that tamed, it worked much better, but I did find that PS gave, overall, slightly better prints on the Prusa.

I do like the 'fuzzy skin' option of Cura, and I find it matches (but does not duplicate) the Prusa textured sheet quite well.  My wife said she could not tell from a quick inspection which was which.  I picked up an Ultimaker printer around the first of this year, and, of course, I use Cura with that.  PS has no profile (that I can find) for the Ultimaker printers.

I've thought of trying to get PS working with the Ultimaker, and what is described above is more or less what I was thinking of trying, basically finding a known-working start-up (and shutdown) gcode section for the desired printer and doing some cut-pastes into PS.  I may be naive, but I would think that once the printer is correctly started and ready to print, the actual 'drawing' of the layers would be more or less standard.  The 'gcode flavor' is one big burning question that I have to answer if I want to go ahead with my challenge.  PS apparently supports quite a few of the common ones.

RE: Please, could someone help me?

As as been noted the placeholders variables are different.

The ones you want to replace are 
M140 S[first_layer_bed_temperature] ; set bed temp
M190 S[first_layer_bed_temperature] ; wait for bed temp
M104 S[first_layer_temperature] ; set extruder temp
M109 S[first_layer_temperature] ; wait for extruder temp

A full list is located here https://github.com/prusa3d/PrusaSlicer/wiki/List-of-all-placeholders-taken-from-the-code (not sure how up to date that is.  Also if you over over settings in PS then many of the tooltips will also display the variable.  There is also a multitool facility that does define the tool using T but I'm not sure of the specifics of that as I dont have a multi tool system.