new install of 1.8.13 on linux works on Uno R3 but not with ATmega2650

Hi all
I just had to reload my computer and upgraded it from Debian Linux version 8 to 10.3 Buster. It is a 64 bit machine.
I used it a long time ago to work on an EFIS (Electronic Flight Information System) project and did a lot of work on coding two different boards. The original source files still do not work on my machine. One is an Arduino Uno R3 and the other is a Geekcreit Mega2650. I worked on a program with the Uno first and tested a lot of stuff I had to make sure it was working. I was trying to make an EFIS for LSA Airplanes with the Mega. I spent hours trying to figure out how the code worked. I gave up really. But now I have reinstalled the new IDE several times today and in different ways. The current result is that the Uno is working when i set up in the TOOLS as a uno and the port as ttyACM0 I can down load sketches to it and they work i think. But when I change the board to Mega2650 and the port to ttySO it will not read the board.

Error message "Native serial port cant obtain info"

When I try to compile anyway I get this message part of it anyway.

avrdude: Version 6.3-20190619
Copyright (c) 2000-2005 Brian Dean, http://www.bdmicro.com/
Copyright (c) 2007-2014 Joerg Wunsch

System wide configuration file is "/home/don/Downloads/arduino-1.8.13/hardware/tools/avr/etc/avrdude.conf"
User configuration file is "/home/don/.avrduderc"
User configuration file does not exist or is not a regular file, skipping

Using Port : /dev/ttyS0
Using Programmer : wiring
Overriding Baud Rate : 115200
avrdude: stk500v2_ReceiveMessage(): timeout
avrdude: stk500v2_ReceiveMessage(): timeout
avrdude: stk500v2_ReceiveMessage(): timeout

Also the ./avrduderc file is not found in the indicated location either. I could not find it any where. Does that make a difference in this case? It does say it is skipping it not crashing because of not finding it.

I think I remember that I had to edit some files to get it to work before but can not remember what ones to look at. I spent the last year and a half building a house and not fooling with computers. Now I want to finish the project. I was pissed at having to reload the machine and lost lots of stuff.
Previous version was 1.6.9 and 1.5.? this one is 1.8.13

I hope this is enough info to get an answer for this. Thanks for any answers.
Don

edit: I read my old posts and the previous version I used was 1.8.5 and was over a year ago.