Reinstalling older versions

When you can't deactivate a serial number (this is the ONLY support Adobe still offers for old programs)
BE SURE TO ONLY ASK FOR ACTIVATION SUPPORT TO ADJUST YOUR ACTIVATION COUNT
You may need to PERSIST or TRY AGAIN to find a support agent with more experience

Be sure to remain signed in with your Adobe ID before accessing the link
Do be aware that Adobe's staffing is impacted by the virus, so wait times are long
-make sure that your browser does NOT block ads, scripts, or pop-ups
-you must also allow 'cookies' in your web browser for the link to work
This link will go directly to the chat option
Type "Agent" in the chat box to bypass the chatbot and be connected to a person
-Meaning type in the word Agent without the quote " " marks
https://helpx.adobe.com/contact.html?rghtup=autoOpen

Adobe does NOT do support by email, so beware of answering anyone who sends you a private message
-click for more information about scammers https://tinyurl.com/10791730

I have Photoshop Elements 2018 and Lightroom 6.14, and need to reinstall both on a new computer. 

---

Running which operating system? Those apps cannot be installed on modern Macs.