I took off some wallpaper & it took off some of the paint- how to fix?

Cut the loose edges from the drywall paper with a utility knife. Sand the edges where paper was removed with a fine-grit sanding pad. Wipe the sanding dust with a clean cloth.

Stir a can of sealing primer with a paint stick. Place a pan liner into a paint pan and fill the pan with primer. Insert a low-nap roller cover onto a roller handle and load the roller with primer. Roll the damaged areas of the drywall with primer and allow it to dry completely.

Apply a second coat of primer and allow it to dry.

Scoop a portion of drywall joint compound out of the container with a taping knife. Hold the knife at a 45-degree angle and spread a smooth layer of compound over the primed areas. This is called skim coating. Wipe the excess off the blade and allow the compound on the wall to dry completely.

Sand the patched areas smooth, using a fine-grit sanding pad. Remove the sanding dust with a whisk broom. Wipe the walls with a clean, damp cloth to remove residual dust.

Apply primer to the skim-coated areas before reapplying texture or paint.

You will have to spackle the wall and then sand it

There is a product made by zinnser. It it called guardz. It is a MUST USE for damaged walls. It will seal any paper exposed. Then you can use drywall mud to smooth over walls. Of course it may take sanding. Then make sure to use a good primer. I recommend 2 coats. The reason wallpaper damages walls was most likely because walls were not properly primed.

Oh and try to scrap off as much loose paint as possible.

That is a big mess! This is the way we used to do it. Scrape off any loose paper/paint. Don't try to remove all of it or force it. Put some drywall patching compound in a paint tray and thin it down with some water to a mayonnaise consistency. Use a low nap roller and spread it on the wall like thick paint. Use a 10" or 12" drywall taping knife and smooth out the compound. Hold the knife at a 45 degree angle and try not leave too many ridges. Let dry overnight. Next day use the drywall knife at a 45 degree angle to scrape off any high spots. Use a damp sponge and go over the compound to smooth it out. Then prime with a stain blocking primer.

I used dry wall mud but didn't sand any off so the wall had a rustic Italian look. Painted over it and it looked great at a much less expensive cost than getting the same look with the special Ralph Lauren paint.

I know this is going to sound "out there" but I love the finish. People pay 100's of dollars to have people texture their walls. You may want to leave it for a week and if you can't imagine it any other way than smooth, by all means take the sage advice above. If it grows on you, I would prime and paint.