Fractal has a manual for the FM3, start there, and begin to learn what you don’t know.
Inside the manual are links to the secondary manuals that cover blocks, using the foot controllers, etc., so read those too.
The wiki, and the technical notes at the top of these forums, are excellent sources of additional details useful to us such as the physics of sound, recording and amplification, electronics and the design of the real amps and devices inside the blocks... it’s really useful information to know because, in general, modelers are not simple standalone devices, and Fractal’s modelers expose more of the inner workings than any other of their competitors. To use one efficiently and effectively we have to know a lot of different things.
Reread them all several times. The manuals are really well written and the others are there to fill in the gaps. I periodically sit down with a cup of tea and pick one and look for something I haven’t learned, simply because there is a lot to know.
The forum is the last place to come after you have exhausted yourself researching in the above mentioned sources of information. Tell us in detail what you things you tried, and provide a block or preset to demonstrate what you did and so we’re all working from the same starting point as you are and to reduce any guessing or suggestions to try previously attempted solutions.