how do i up grade my premium membership

[Syo Emerald]

You can not upgrade the Linden Home. The sim your house is on can only contain a certain amount of prims and those are divided equally between all the Linden Homes on the sim. So there is no upgrade possible. The intention of the Linden Home is to provide premium members with an easy and simple starting home.

Everything above this basic level requires to invest into own land. If you make that step, getting rid of your Linden Home is also adviced, because instead of it you can get the first 512m of land rented from LL without any extra costs.

[Syo Emerald]

You can not upgrade the Linden Home. The sim your house is on can only contain a certain amount of prims and those are divided equally between all the Linden Homes on the sim. So there is no upgrade possible. The intention of the Linden Home is to provide premium members with an easy and simple starting home.

Everything above this basic level requires to invest into own land. If you make that step, getting rid of your Linden Home is also adviced, because instead of it you can get the first 512m of land rented from LL without any extra costs.

[Rolig Loon]

You have more than one misunderstanding. 

1. The only way to get a larger land impact allowance (L.I. = prim allowance) is to own more land.  That's the way SL works.  You get one more prim for every 4.37 sq m you own.

2. You cannot buy more land for your Linden Home.  All Linden Homes are on identical 512 sq m parcels, so you have exactly 117 L.I.  If you want more land, you'll have to abandon your Linden Home and use your Premium land fee waiver to get a larger parcel somewhere else on the Mainland.  (Remember that a Lindeon Home does not count against the L.I. on its parcel, but anything you put on your own parcel elsewhere -- including a house -- does count.)

3. The place where you clicked a button to increase prims doesn't actually do anything. When you use it, you are essentially setting a limit for yourself.  If you go to buy land and the purchase will potentially exceed the limit you set, you will get a warning message.  That's all.  It's like setting your alarm clock or your burglar alarm.  If you clicked the 1024 sq m button, you may buy up to 1024 sq of land without tripping the alarm.

4.  Finally, you can't upgrade your Premium membership.  There's no more "up" than that (well, unless you have a corporate account).

Read  https://community.secondlife.com/t5/English-Knowledge-Base/Premium-membership/ta-p/1054477 and https://community.secondlife.com/t5/English-Knowledge-Base/Linden-Homes/ta-p/700103 and https://community.secondlife.com/t5/English-Knowledge-Base/Buying-land/ta-p/700043 and consider taking Lindal Kidd's free class in land ownership and management at Caledon Oxbridge University, in world, on Friday at 5 SLT.