Built app for tablets/pc browser; only advertising on youtube shorts/instagram reels ; get ~1k-5k views per video. But all mobile ; death?

This is my first attempt at a product and it's 90% to the version 1 phase so I need to validate it with some subscriptions asap before moving onto version 2 expanding it. The app seems good to me. But I'm not sure how to advertise it other than make videos of the app for short form content. I get views, likes, and subscriptions steadily each time I post , but actual visits to the website is low and no email sign ups yet… According to youtube stuido its 90% mobile phones watching the clip so there's a gap between the phone and the browser/tablet usage.

Do I post my short videos elsewhere? Do I 'call to action' ask them to comment on the video and hope they do so I can just send them the link that's in my bio with additional short explanation? My videos are very short like 20-40 seconds to keep the % watched high.

I'm not sure what I'm doing but i want sales given how deep I am in this product which I've been using myself with good effect.