There probably isn't much you can do unless you have or learn fab skills. I may be wrong but I doubt that major aftermarket companies are willing to waste time on a rav 4. They aren't exactly known for offroading more like what someone buys their daughter for graduating.
My friend had a 1st gen a long time ago like 10th grade, we took it out to the Ozarks to rescue a friend that joined a cult deep in the backcountry, we ended up stuck in some door sill deep for the rav mud, it took a few hours of collecting stuff to jam under the tires to get traction on the awd system but we finally did and it popped out. We got back to Texas without any other issue but when we got back to my freinds house we learned how lucky we were, under that mud we were stuck on a tree stump that wrecked the oil pan on impact.
To sum it up it can be done but I wouldnt recommend it. Go have fun with it just don't expect it to be a jeep, truck or suv with truck frame, and the biggest thing to remember is it is not a true 4x4 so drive accordingly.