Is it possible to get my pictures out of Iphoto and into Photos after I have updated to Catalina?

Yes.

Hold down the option (or alt) key and launch Photos. From the resulting menu select 'Choose Library' and point at your iPhoto Library. It will do the rest.

How do I get LinkeIn to work again after upgrade to Catalina?

As that query has nothing to do with iPhoto I'd ask that on a forum about web browsing.