This is the perfect occasion to retain a lawyer, whether a solicitor or a barrister, for advice.
Retaining a solicitor has the added advantage of the solicitor being able to act for you in further negotiations and, if you provide instructions and authority to do so, sign the contract on your behalf (a barrister cannot generally do so due to the nature of their profession and work.)
You should not feel forced to agree to a contract that you do not understand and you always have the option of reviewing the contract, coming back later, and even suggesting amendments that might make the contract fairer. Signing a contract has important legal consequences and you should not do so unless you understand the contract and / or have been advised by a lawyer as to what the contract means.
Disclaimer: This advice is general and is not intended to be relied upon as advice for your specific situation and circumstances. In order to provide an advice taking into account the entirety of your unique circumstances, I would strongly recommend that you seek further professional legal advice.