Welcome to the gamedata editing tutorial for srb2 versions 2.2.x so let's get started.
side note-this may work for earlier ports of srb2 but there's less help when it comes to that stuff.

expectations- you require something like z archive or rar and also don't be an idiot so don't be that person who's like
Quote Originally Posted by what the dumbass would say
whoops looks like I accidentally deleted my downloads folder
so don't be him. Sorry if that was rude but I had to get the point across.

step 1-
get a mobile port (no duh)
step 1.png
preferably get it from SRB2.org because it's the easiest to work with.
also please follow the installation instructions accordingly.

step 2-
once installed go into the Android folder for srb2
step 2.png
and before the idiot in the corner asks yes this is in the Android folder unless you have a terrible port which is why I suggested the official srb2.org download.

step 3-
search for the gamedata.dta folder and remove or just move it out of the Android folder.
step 3.png
please note that saves made for other mods will not conflict because they are entirely different save files but changing those save files is a whole other thing so go get help from someone else about that stuff.

step 4-
get your save file.
step 4.png
The best save file I know of is at speedrun.com because they hand out a 100% save file for srb2, hand out mods for srb2, and hand out srb2 mod save files plus it won't be getting taken down anytime soon.

step 5-
cut/copy and paste it into the srb2 Android folder.
step 5.png
don't worry about file placement because it will usually do it for you unless you have an unafficial crappy port which all I can say is use the official port.

hooray you did it so now you've skipped playing the entire game so enjoy messing around with all the fun cool stuff.