Because of the lower half of your spider body being about 10 feet in diameter and you hight usually reaching about 8 feet your size is Large

Dreilka are swift hunters but can barely swim

Your base walking speed is 40

Your base climbing speed is 50

Your base swing seen is 10

Your base burrowing speed is 0

Your base fly speed is 0

Dreilka mature much faster than humans becoming full grown and only 3 years after being born and can live a very long time, so long as they stay fed well no one knows how long they live but some have bin reported to live over hundreds of years

Dreilka despite there size  are very agile Hunters and can see things other would miss

You get a plus 2 to dexterity

You get a plus 1 to wisdom

And because of your frightening appearance you get a negative -1 to your charisma

You also gain Proficiency in

Intimidation and Athletics

Dreilka have a potent Venom that can Rend creatures who aren't immune to poison stunned they can only produce so much in a day and must make a long rest to regain more Venom can be applied via a bite or if applied to projectiles like arrows or crossbow bolts if applied to said projectiles it will only last 1 minute on said projectile 

As a action you can make a bite attack at creatures who are within 5 feet of you the bite attack is a plus 3 to hit and does 1d4 piercing damage at first to fith level 2d4 piercing damage at fith to tenth level 3d4 at tenth to fifteenth level 4d4 at fifteenth level to twentieth level and 5d4 at twentieth level

On a successful bite if the creature isn't immune to poison it must make a constitution saving throw of at least 10 or be stunned for 30 secs

Dreilka can spinn webs much like there Drider father's and get better at it the older they get but can only spin so much Web per day before they need to take a long rest to regain more

At level one as a action you can cover 4 5ft tiles at level 1 per long rest you can can cover two more five feet tiles per level for example at level 5 you can cover 9  5 feet tiles with web

Dreilka webs are sticky and anything that tries to walk over them that is not considered a spider consider moving on the webs as difficult Terrain however Dreilka move faster on the webs by 10 feet and gain Proficiency in stealth while on any webs 

Dreilka can try to wrap up creatures large or smaller in webs by spending 2 5ft tile for  large creature's and 1 5ft tile for medium and small creatures Dreilka don't have to spend any of these on tiny creatures first the creature must be within 5 feet of you you could attempt to make a grapple check against the target using Athletics with either Dex or strength modifier  on the first successful grapple the Target is considered grappled and must make a strength saving throw or Dex saving throw of at least 14 to break out of the webs if the first grapple was successful as another action you can attempt to Grapple again wrapping up the target further on another successful grapple attempt the target is considered restrained and to try to break the second successful grapple the target must make a strength saving throw of at least 16 to break out of the thicker webs and if the second grapple is successful you can attempt to use an action for a third grapple and on a successful third grapple the target is considered stunned and completely wrapped up before the third grapple  the target must make a successful strength saving throw of 18 or be completely wrapped up

You you don't need to make these grapple checks if the target is already stunned or asleep