Start the build outside of the case, use the box the motherboard came in as a table. Install the cpu, ram, hook up the psu (fully modular if your budget allows), power on and make sure all works. Easier to troubleshoot this way.

On Windows:

• Bitwarden, password manager (FOSS, but paid account or contribution(s) made - support development!)
• Advanced Renamer, just what it says (FOSS, but paid account or contribution(s) made - support development!)
• FreeFileSync, terrific file sync app (FOSS, but paid account or contribution(s) made - support development!)
• VLC, media player
• WizTree, folder comparison (FOSS, but paid account or contribution(s) made - support development!)
• Notepad ++, use it everyday (FOSS, but paid account or contribution(s) made - support development!)
• Everything, ditch Windows Search!
• Plex, Emby, Jellyfin for media streaming (Jellyfin is FOSS, Plex can be free, Emby??? - have Plex and Emby Lifetime accounts)
• caddy server, easy to set up and use

Android:

• FairEmail - best email client around (FOSS, but paid account or contribution(s) made - support development!)
• nzb360 - monitor all your arr apps (FOSS, but paid account or contribution(s) made - support development!)
• Tautulli - Plex stats on steroids (Android, plus also on Windows)
• Nova, great launcher (FOSS, but paid account or contribution(s) made - support development!)
• Standard Notes FOSS, but paid account or contribution(s) made - support development!)
• Authy
• Boost, soon to be gone thanks to reddit CEO
• Sports Alert (FOSS, but paid account or contribution(s) made - support development!)

Probably missed some, but the above are essential to my everyday use.