qBittorrent definitely.
Free and open source, no adult/betting ads that you have to pay for an ad free version if you don't want to see them, not installing adware either.
I find Deluge to be a nice, cross platform client. The Windows version was finally bumped to 2.X. The client has integrated VPN functionality but I'm not sure if that's really a big deal for today's landscape
qbittorrent has it's own internal search with plugins, and also can connect with jackett.
this way you can search torrents from inside qbittorrent directly.
Everyone's said qBittorrent, and I agree. I found myself using an old build of uTorrent for a very long time (2.2.1, I believe). I finally realized it was probably a risk being so far behind. qBittorrent feels like old uTorrent, before it got extra bloated and scummier. It also adds a lot of features. Truly, qBittorrent is the answer you're looking for coming from uTorrent.