How to create view joining two table of similar records without duplicating.

SAGAR1985 I think I might see where the issue lies.

Your query for the [dbo].[ARC_Skill] table is selecting distinct Personal_IDs, meaning you are counting unique IDs. If there's duplicates, you're not seeing them.

select distinct Personal_ID from [dbo].[ARC_Skill] where Calendar_day = '2024-05-31';
--42678 rows

If you do the following queries, I believe you'll find that you have the same amount of duplicates in both your tables:

Select 
	Personal_ID, /* The personal_ID */
	Calendar_day, /* The calendar day */
	Count(Personal_ID) as NumberOfDuplicates /* Number of rows with this given Personal_ID and Calendar_day */
from [dbo].[ARC_SKILL]
where Calendar_day = '2024-05-31'
Group By Personal_ID, Calendar_day /* Grouping enables counting rows pr. Personal_ID */
Order by NumberOfDuplicates Desc /* Largest number on top */
/* You may have to use 'order by COUNT(Personal_ID) desc' instead */

Select 
	Personal_ID, /* The personal_ID */
	Calendar_day, /* The calendar day */
	Count(Personal_ID) as NumberOfDuplicates /* Number of rows with this given Personal_ID and Calendar_day */
from [dbo].[Skill_Analysis]
where Calendar_day = '2024-05-31'
Group By Personal_ID, Calendar_day /* Grouping enables counting rows pr. Personal_ID */
Order by NumberOfDuplicates Desc /* Largest number on top */
/* You may have to use 'order by COUNT(Personal_ID) desc' instead */

In your counting table at the end, we see the columns

This means you've accidentally gotten a cartesian cross product where your tables contain the same amount of duplicates for the combination of [Personal_ID] and [Calendar_day].

For RL '51512295', that means all 11 rows with a given [Personal_ID] and [Calendar_day] in [ARC_Skill] has been matched separately with all 11 rows with the same [Personal_ID] and [Calendar_day] in [Skill_Analysis]. 11*11 = 121.

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In conclusion, [Personal_ID] and [Calendar_day] are not sufficient to uniquely match between these tables.
I hope there's another column you can add in the join predicate in order to get the expected result.