Since it is my first question in the forum, I write more details below.
* I am Auslander and I had almost worked for more than 5 years in full time employment with blue card as a software engineer. I have a Bluecard with “niederlassungerlaubnis” - settlement permit status in Germany. I changed the status after completing 3 years. Last month i register in Arbeitsamt as Arbeitlos and receiving ALG as my full time employment finished by may.
* Recently i received an offer for freelance for few months only (7–8 months) in another Europe country.

My questiosn are -

1. I would like to have full time employment after 8 months In this case is it good advice to take this freelancing opportunity?

2. Do i need to reprocess my blue card in the european country where i will be working for the client?

3. Does my Niederlassungserlaubnis status will be affected due to temporary freelancing work for 7 to 8 months?

4. Currently, I have a TK public heath insurance. Does this needs to be changed?

5. The work will be offered by a consulting agency from UK. Any specific concerns regarding tax ?

I would be pleased to know the answers early from experts. thank you very much

"1. I would like to have full time employment after 8 months In this case is it good advice to take this freelancing opportunity?", why not, nothing can stop you doing it but you have to register at Finanzamt and notify your Arbeitsamt.
"2. Do i need to reprocess my blue card in the european country where i will be working for the client?", I don't think so but if it is freelance, can you do it remotely?
"3. Does my Niederlassungserlaubnis status will be affected due to temporary freelancing work for 7 to 8 months?", no
"4. Currently, I have a TK public heath insurance. Does this needs to be changed?", not really, but you have to notify them. If your revenue will solely come from your freelance work, you have to change your status to "freiwillige versichert"
"5. The work will be offered by a consulting agency from UK. Any specific concerns regarding tax ?", no, except that you won't be charging them VAT and you will be paying your tax on your revenue here in Germany.

D.