Most videos are already in the lossy codec, the only use for lossless is in professional production where videos are exported as image sequences for editing. You're guarantee to lose quality with each time encoding/compressing the videos with usual codec settings
The loss can be controled by specifying encode parameters. You can set these in Handbrake but I recommend you learning about ffmpeg, it is also the transcode engine used underneath Handbrake. This tool have steep learning curve for non-tech people due to its command-line interface (need to know the basics of terminal command-line, in Windows you use command prompt for that) and need some understanding about video file like encode/decode, crf, bitrate, codec, container...
Despite that it is totally worth diving into the rabbit hole because ffmpeg can do lots of useful process on media files like lossless cut/merge videos, extract images, change fps... The tool can be used on mac, windows, linux and android.
I still highly recommend using ffmpeg on your laptop because the specs is better and is easier to use than on android phone (to install ffmpeg on android you'll have to install
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first, then search and install termux app within f-droid, then type the command "termux-setup-storage" to give termux access to your storage, then install ffmpeg by typing "pkg install ffmpeg" in the termux app. Not to mention needing another file browsing app like Material Files for copying file path to use with ffmpeg commands)