For the former, please add a screenshot / screencaptured video showing all the tracks, the position of the playhead and the hotkey to select to right. As a preliminary check, please ensure the auto-select is enabled on all tracks.
For the latter, when observed, please grab logs after restarting Resolve from the Help menu. More information on your system will definitely help. Along with the info requested in the FAQs, please also indicate your display resolutions and scaling.
Please create a shareable link from Dropbox, One Drive or othr file share services if the files cannot be attached to the post.
Thanks
Shrinivas