If both database on same server. You can check similar tables by using following query :
select
fdb.name, sdb.name
from
FIRSTDBNAME.sys.tables fdb
join SECONDDBNAME.sys.tables sdb
on fdb.name = sdb.name -- compare same name tables
order by
1
By listing out similar table you can compare columns schema using sys.columns
view.
Hope this helps you.