here what I've done:

maria@maria-Aspire-A315-41:~$ sudo dpkg --add-architecture i386
[sudo] password for maria:
maria@maria-Aspire-A315-41:~$ wget -nc https://dl.winehq.org/wine-builds/Release.key
--2020-08-05 22:56:26-- https://dl.winehq.org/wine-builds/Release.key
Resolving dl.winehq.org (dl.winehq.org)... 151.101.178.217
Connecting to dl.winehq.org (dl.winehq.org)|151.101.178.217|:443... connected.
HTTP request sent, awaiting response... 200 OK
Length: 3122 (3,0K) [application/pgp-keys]
Saving to: ‘Release.key’

Release.key 100%[===================>] 3,05K --.-KB/s in 0s

2020-08-05 22:56:26 (31,8 MB/s) - ‘Release.key’ saved [3122/3122]

maria@maria-Aspire-A315-41:~$ sudo apt-key add Release.key
OK
maria@maria-Aspire-A315-41:~$ sudo apt-add-repository https://dl.winehq.org/wine-builds/ubuntu/ -y
Hit:1 http://br.archive.ubuntu.com/ubuntu focal InRelease
Get:2 http://br.archive.ubuntu.com/ubuntu focal-updates InRelease [111 kB]
Ign:3 http://ppa.launchpad.net/paolorotolo/droidcam/ubuntu focal InRelease
Get:4 http://br.archive.ubuntu.com/ubuntu focal-backports InRelease [98,3 kB]
Get:5 http://security.ubuntu.com/ubuntu focal-security InRelease [107 kB]
Get:6 https://brave-browser-apt-release.s3.brave.com stable InRelease [4.316 B]
Get:7 https://dl.winehq.org/wine-builds/ubuntu focal InRelease [6.257 B]
Get:8 http://br.archive.ubuntu.com/ubuntu focal-updates/main amd64 DEP-11 Metadata [196 kB]
Err:9 http://ppa.launchpad.net/paolorotolo/droidcam/ubuntu focal Release
404 Not Found [IP: 2001:67c:1560:8008::15 80]
Get:10 http://br.archive.ubuntu.com/ubuntu focal-updates/main amd64 c-n-f Metadata [8.160 B]
Get:11 http://br.archive.ubuntu.com/ubuntu focal-updates/universe amd64 Packages [149 kB]
Get:12 http://br.archive.ubuntu.com/ubuntu focal-updates/universe i386 Packages [82,4 kB]
Get:13 http://br.archive.ubuntu.com/ubuntu focal-updates/universe Translation-en [74,3 kB]
Get:14 http://br.archive.ubuntu.com/ubuntu focal-updates/universe amd64 DEP-11 Metadata [177 kB]
Get:15 http://br.archive.ubuntu.com/ubuntu focal-updates/universe DEP-11 48x48 Icons [92,2 kB]
Err:7 https://dl.winehq.org/wine-builds/ubuntu focal InRelease
The following signatures couldn't be verified because the public key is not available: NO_PUBKEY 76F1A20FF987672F
Get:16 http://br.archive.ubuntu.com/ubuntu focal-updates/universe amd64 c-n-f Metadata [5.060 B]
Get:17 http://br.archive.ubuntu.com/ubuntu focal-updates/multiverse amd64 DEP-11 Metadata [2.468 B]
Get:18 http://br.archive.ubuntu.com/ubuntu focal-backports/universe amd64 DEP-11 Metadata [1.976 B]
Get:19 http://security.ubuntu.com/ubuntu focal-security/main amd64 DEP-11 Metadata [21,2 kB]
Get:20 http://security.ubuntu.com/ubuntu focal-security/main amd64 c-n-f Metadata [3.952 B]
Get:21 http://security.ubuntu.com/ubuntu focal-security/universe amd64 Packages [52,2 kB]
Get:22 http://security.ubuntu.com/ubuntu focal-security/universe i386 Packages [23,9 kB]
Get:23 http://security.ubuntu.com/ubuntu focal-security/universe Translation-en [26,6 kB]
Get:24 http://security.ubuntu.com/ubuntu focal-security/universe amd64 DEP-11 Metadata [35,9 kB]
Get:25 http://security.ubuntu.com/ubuntu focal-security/universe DEP-11 48x48 Icons [7.192 B]
Get:26 http://security.ubuntu.com/ubuntu focal-security/universe amd64 c-n-f Metadata [2.108 B]
Reading package lists... Done
E: The repository 'http://ppa.launchpad.net/paolorotolo/droidcam/ubuntu focal Release' does not have a Release file.
N: Updating from such a repository can't be done securely, and is therefore disabled by default.
N: See apt-secure(8) manpage for repository creation and user configuration details.
W: GPG error: https://dl.winehq.org/wine-builds/ubuntu focal InRelease: The following signatures couldn't be verified because the public key is not available: NO_PUBKEY 76F1A20FF987672F
E: The repository 'https://dl.winehq.org/wine-builds/ubuntu focal InRelease' is not signed.
N: Updating from such a repository can't be done securely, and is therefore disabled by default.
N: See apt-secure(8) manpage for repository creation and user configuration details.


I can't figure out what is the problem to solve that, please help me

I want to install that so I can install and play AM2R

The error message in your thread title has nothing to do with Wine. It's about droidcam PPA. Get rid of it it with
Now to your problem.
You added Release.key from WineHQ to Ubuntu keyring, but their download instruction mentions winehq.key instead:

about that should I do all the same steps over again or just copy and paste on an empty terminal?