Libreoffice official website
Package download address

Download Package

# Install the package
mkdir libreoffice && cd libreoffice
wget https://fastmirror.pp.ua/tdf/libreoffice/stable/7.6.1/deb/x86_64/LibreOffice_7.6.1_Linux_x86-64_deb.tar.gz
tar -zxvf LibreOffice_7.6.1_Linux_x86-64_deb.tar.gz
cd LibreOffice_7.6.1.2_Linux_x86-64_deb/DEBS/
sudo dpkg -i ./*.deb

Open the program

libreoffice7.6
Or
/opt/libreoffice7.6/program/soffice

install Languare Package

cd ../../
wget https://mirrors.gethosted.online/the-document-foundation/libreoffice/stable/7.6.1/deb/x86_64/LibreOffice_7.6.1_Linux_x86-64_deb_langpack_zh-CN.tar.gz
tar -zxvf LibreOffice_7.6.1_Linux_x86-64_deb_langpack_zh-CN.tar.gz
cd LibreOffice_7.6.1.2_Linux_x86-64_deb_langpack_zh-CN/DEBS
sudo chown _apt ./*
sudo apt install -y ./*.deb