do sinusitis and tonsilitis effect the functioning of thyroid gland?

Hello and welcome to EmpowHer,
There are 3 main causes of hyperthyroidism, none if which are related to the tonsils or sinuses.
--Grave's disease: an autoimmune disorder
--Hyperfunctioning thyroid nodules (toxic adenoma, toxic multinodular goiter, Plummer's disease): This form of hyperthyroidism occurs when one or more adenomas of your thyroid produce too much T-4. An adenoma is a part of the gland that has walled itself off from the rest of the gland, forming noncancerous (benign) lumps that may cause an enlargement of the thyroid. Not all adenomas produce excess T-4, and doctors aren't sure what causes some to begin producing too much hormone.
--Thyroiditis: Sometimes your thyroid gland can become inflamed for unknown reasons. The inflammation can cause excess thyroid hormone stored in the gland to leak into your bloodstream. One rare type of thyroiditis, known as subacute granulomatous thyroiditis, causes pain in the thyroid gland. Other types are painless and may sometimes occur after pregnancy (postpartum thyroiditis).

So, removing your tonsils will not effect your thyroid. I highly suggest that you speak with your doctor about learning the cause of your hyperthyroidism to assess the best treatment for you.
Faith