Help! The toilet is plugged up!? Flushed regular stuff down the basement toilet,toilet daily,solid waste,and the solution waste.muse...

Flushed regular stuff down the basement toilet,toilet daily,solid waste,and the solution waste.muse there be too much solid waste,and toilet plugged.Used plunger,hoping it would work but it didn't.When I flushed again,trialling,the leftover wet was pushed down,but come back up,mixing beside water coming down,and notice that the water that come down was a great deal more than the usual gallons of water used to flush a toilet.deliberate it was the marine that I had pushed down using the plunger.When checked the key floor toilet,(dad using the plunger to try and push the water)the a little of the marine was coming to that toilet.The upstairs toilet be ok,and nothing be wrong with that.When flushed the upstairs toilet 2x or something,after flushed the major floor toilet about 3,2x the hose that had go down with the poo come to basement toilet.reversed.Water surrounded by basement toilet is to the top of toilet immediately.When u flush(tank)usually the water contained by tank be in motion down but when i flushed, water go up or stayed.
Above Ground Pool Backfill and Deck Questions?
Answers:    DIG IN TO THAT POO WATER!!! j/k call a the mario brothers... they are plumbers
What's the best method...?
Call a plumber.