How to fix a deep link from a web to an app that redirects to the store or if there is an app redirects to the corresponding content similar to reddit

Question

i use node-deeplink lib but in safari and android not working. i want similar deep linking with reddit. If you have an app, go to the app with the same content as on the web, but if you don't have the app installed, it goes to the store to download. I have 2 links (1 link to the store and 1 link is app://...{code})