see this link:
https://turbotax.intuit.com/tax-tips/investments-and-taxes/capital-gains-and-losses/L7GF1ouP8
1) they don't have to be of the same type. The profit on the House sale and the stock market transactions all end up on Schedule D. Read the link
2) Yes, but note that if losses exceed gains, only $3000 can be deducted on the tax return; the rest is deferred into the future.
