Go find Delawareandlehigh.org and study all that first. Very helpful info and current. No, there are still trail sections not completed and the stretch from Allentown to Northamption is on road and, I hear, not fun. Sections north of White Haven are rocky single track or just conceptual.

I rode the D&L on Tuesday from Cementon to White Haven and it was really great. My first Century on a mtn bike. I actually rode about 3 miles north of White Haven, into the woods, to reach the 50 mile point before I turned for home. I hear the trail continues to be rough single track north of that. Study their website. AFAIK, none of the trail is closed due to COVID though many of the rest rooms n out houses and water supplies are still closed. Best to ride self supported. I carried 60ml of water (drank it all) and stashed another quart in my car, which I guzzled when I got back there.