Please help. I don't understand what I am doing wrong

My prints keep turning out like this (See attached images) and I seriously don't understand what I am doing wrongPrinter is a Snapmaker 350, fillament is PLA, software is Snapmaker Lurban and designs are made in TinkerCadI have been trying to play around with the different settings...setting infill to 100% and different layer thickness etc.....it has made a little difference but its still looks like anus..I have been experimenting with turning the nozzle temperature up as well an lowering the work speed to 75%, neither of which seem to have made any difference.Please help, I really don't understand what I am doing wrong

I forgot to mention; the initial layers look fine...but its the rest of the print that turns out terrible

First point, one hundred percent infill isn't going to make the part stronger than a lower value. One can have as low as 20 to 25 percent infill and have a fairly strong part, which is more dependent on the number of perimeters and base and top layers. To ensure that your temperature is correct, consider to download a temperature tower and adjust the layer temperature values to match. This will give you a fairly strong start on the temperature range you can use. Also, the last panel is unreadable, so one cannot determine your print speed. Having good first layers and poorer ones later implies too fast or too cold or both. The temperature tower will help determine that and get you closer to a solution. It's difficult to determine if your slicer software is a Cura clone, but it's certainly possible. You'll have to search for "how to configure temperature tower in Cura" to perform the somewhat tedious process of getting those values correct. When you reference seventy-five percent work speed, it's meaningless without a base value. For PLA, you should be able to print in the fifties range or even higher if all things are correct. As part of the troubleshooting, drop the speed to the low forties. That's 40 mm / second printing speed. As an additional step, extrude a string of filament and examine it for bubbles. If there's any moisture in the filament, all bets are off. You'll find two side of this argument. There are posts from people who print with two year old unprotected filament with zero problems and others with fresh from the box filament that has to be dried in order to create anything worth keeping. It can't hurt to dry your filament, but if you don't have a dehydrator (lowest cost method) or a dry-box, just get the rest of the tests completed.