Piped for desktop would be a better option for youtube imo, but really depends on which “Big tech company” you’re trying to hide from and what information do you want to share with them. For example, Google probably has your ip tied to your gmail account, which has whatever information you used, since you didn’t use a vpn when first creating it. Also unless you disabled the bloatware via adb that came with your xiaomi device some other third party company may also have your ip and whatever info you inputted into those apps, if at all. Again just depends on what you want so your setup might be fine.
Edit: if wanting to protect from google then your mobile device is the biggest issue. Getting an always on vpn is a must (look at proton or mullvad), remove your personal account and create a burner with fake info and use something like aurora store with that burner account should help a lot. Would be really inconvenient if you still use your personal gmail account so maybe before doing anything start migrating to a different email provider
Edit 2: if protecting from meta then facebook messenger is the biggest issue. Getting an always on vpn that comes bundled with protection from trackers/ads (mullvad and proton i think does this) maybe your best choice unless you want to recreate your account and lose all of your contacts/messages which would be really inconvenient. So just treat facebook messenger like a public forum and dont give up too much info. If its possible maybe use a hardened browser, like mull +ublock, instead to use facebook messenger again if thats possible