For Debian 10, you need to add the backports repo

sh -c "echo 'deb http://deb.debian.org/debian buster-backports main contrib non-free' > /etc/apt/sources.list.d/buster-backports.list"
apt-get update

Install Wireguard Tools

apt install wireguard-tools

Get current golang

wget https://golang.org/dl/go1.15.1.linux-amd64.tar.gz
tar xvf go1.15.1.linux-amd64.tar.gz
sudo mv go /opt/go1.15.1
sudo ln -s /opt/go1.15.1/bin/go /usr/local/bin/go

Get wireguard go

cd /usr/local/src
wget https://git.zx2c4.com/wireguard-go/snapshot/wireguard-go-0.0.20200320.tar.xz
tar xvf wireguard-go-0.0.20200320.tar.xz
cd wireguard-go-0.0.20200320

Compile

make

Install

sudo cp wireguard-go /usr/local/bin