wget https://www.python.org/ftp/python/3.8.3/Python-3.8.3.tgz
Have unzipped Python-3.8.3.tgz and after unzip ,folder not has bin folder
Have copied unzipped Python3.8.3 from working Oracle Linux Server 7.6 server and ran python3 or python8.3 but saying command not found
Not sure where you put the unzipped python directory, but unless you added that directory is in your path you will need to run it like this from current directory
./python3
# or
./python3.8
Or add the unzipped directory to path.
# for current session only
export PATH=$PATH:/your/unzipped/python/dir
# to add permanently
echo 'export PATH=$PATH:/your/unzipped/python/dir' >> ~/.bashrc
# or ~/.bash_profile